Over the past three days, there have been a series of deadly incidents on the route to an aid distribution site in Gaza run by a controversial group backed by the US and Israel.

The three incidents took place on roads approaching one of the new sites in the extreme south-west of Gaza, which is under full Israeli military control. The facility is being operated by the Gaza Humanitarian Foundation (GHF).

The first incident took place early on Sunday morning when 31 Palestinians were killed by Israeli fire, according to the Hamas-run Civil Defence agency. Another three people were killed by gunfire on Monday morning, according to the International Committee of the Red Cross (ICRC).

Meanwhile, a further 27 people were killed by Israeli fire near the site on Tuesday morning, according to health officials.

Israel has denounced what it called “false reports” that its troops fired on civilians at or near the sites. It said that some soldiers fired warning shots on Sunday 1km away, and that they also opened fire after identifying “several suspects” on Monday and Tuesday.

Very few videos have emerged from Gaza that show the incidents themselves, but BBC Verify has examined available footage and attempted to map how they unfolded.

All three are reported to have taken place near an aid distribution centre in the south-west of Gaza, in the Tal al-Sultan area.

The site, named Safe Distribution Site 1 (SDS 1) by the GHF, opened on the 26 May. It is one of four such facilities, three of which are based in southern Gaza.

The facilities are part of a new aid system – widely condemned by humanitarian groups – aiming to bypass the UN, which Israel has accused of failing to prevent Hamas diverting aid to its fighters. The UN says that has not been a big problem and that the GHF’s system is unworkable and unethical.

However, only SDS 1 has been open and operational since Friday, according to official GHF posts online. It follows a chaotic opening week which saw the site overrun by desperate civilians, and projectiles being thrown towards Gazans at another facility at the GHF’s northern site near Nuseirat on Thursday.

A spokesperson for the foundation did not respond to messages asking why the other facilities have been closed for several days.

The GHF has also encouraged civilians to follow a set route when approaching SDS 1, directing them along a coastal road called al-Rashid Street.

The instructions have been issued on the foundation’s official Facebook page.

Chris Newton, a senior analyst at the Brussels-based think tank Crisis Group, said the route was neither “safe nor effective”.

He added that directing civilians down a single route towards the site was “a very far cry from what was possible” under the UN-based system, which saw 400 distribution points scattered across the strip.

“This all looks designed to fail,” he said of the new aid system.

According to the Hamas-run Gaza health ministry, some 31 people were killed by gunfire on Sunday.

The GHF posted on its official Facebook page early on Sunday, telling civilians that SDS 1 would be open from 05:00 local time.

However, just an hour later it posted again saying that the site was closed. By this time many Gazans had gathered at the Al-Alam roundabout as they waited to be granted access to the site, Mohammed Ghareeb, a journalist based in Rafah, told the BBC.

We have seen a limited amount of video that is claimed to relate to the shootings. In one video filmed on the route to the aid site, purportedly on Sunday, people lie on the ground and an explosion is heard.

There is a “realistic possibility” this blast sound was a battle tank firing its main armament, says David Heathcote, an intelligence manager with security analysts McKenzie Intelligence, but he adds that “there could be other explanations”. Another expert we spoke to said the source of the sound was unclear.

An audio recording provided to the BBC by international staff at the UK-Med field hospital about 3km away from the site captured two apparent explosions and protracted gunfire for over five minutes.

Video footage posted at 06:08 showed dozens of people lying prone on sand, with automatic gunfire audible. BBC Verify could not definitively geolocate the footage.

Another clip reviewed by BBC Verify, which claimed to be from the aftermath of the incident, showed a number of bodies lying on a beach on Gaza’s coast. As the video progresses, several of the bodies were covered by white bags. One of those lying on the beach appeared to be a young woman.

We cannot definitively geolocate the footage. However, lights seen in the distance suggest that the footage may have been filmed in an area about 1km from SDS 1.

Images – provided to the BBC by doctors – of bullets recovered from those killed and wounded in the incidents showed that both 5.56mm and 7.62mm rounds were used.

But Benedict Manzin – an analyst with the risk consultancy Sibylline – said that the source of the rounds was unclear, noting that both the Israel Defense Forces (IDF) and Palestinian armed groups “will have access to weapons that fire 5.56mm and 7.62mm rounds”.

The IDF denied its troops fired at civilians “near or within” the site and said reports to this effect were false. But an Israeli military source later said warning shots were fired approximately 1km (0.6 miles) away from the site “to prevent suspects from approaching the troops”.

The GHF said in a statement: “There were no injuries, fatalities or incidents during our operations yesterday. Period. We have yet to see any evidence that there was an attack at or near our facility.”

On Monday, three people were killed while waiting for food near SDS 1, according to the ICRC.

The Israeli military said “warning shots were fired toward several suspects who advanced toward” troops approximately 1km from the site.

The Gaza health ministry said at least 27 people were then killed when Israeli forces opened fire near SDS 1 early on Tuesday.

Very little footage has emerged purporting to show the moment of the shooting. But one clip posted online showed people running with gunfire audible. BBC Verify geolocated the footage to a road near SDS 1 and established it was newly published on Tuesday although we cannot say for certain it relates to Tuesday’s incident.

Mahmoud Basal, a spokesperson for the Palestinian Civil Defence agency, told the BBC that the incident again occurred a few hundred metres away from the Al-Alam roundabout. He said most of those killed or injured “were hit by gunfire from tanks, helicopters and quadcopter drones”.

Yasser Abu Lubda, a 50-year-old who has been displaced from Rafah, told the Associated Press (AP) news agency that the shooting began shortly before 04:00 local time. Rasha al-Nahal, another witness, told AP “there was gunfire from all directions”.

And the ICRC said in a statement that its field hospital in Rafah received “a mass casualty influx of 184 patients”.

“This includes nineteen cases who were declared dead upon arrival and eight more who died due to their wounds shortly after. The majority of cases suffered gunshot wounds.”

In a statement, the IDF said approximately 0.5km from the aid distribution site “several suspects” moved towards them. It said troops shot warning fire and when “suspects failed to retreat, additional shots were directed near a few individual suspects”. It said it was looking into reports of casualties.

Responding to Tuesday’s incident, the GHF said: “While the aid distribution was conducted safely and without incident at our site today, we understand that IDF is investigating whether a number of civilians were injured after moving beyond the designated safe corridor and into a closed military zone. This was an area well beyond our secure distribution site and operations area.”

BBC Verify will continue to investigate footage surrounding each of the three incidents.

Reporting and verification by Matt Murphy, Mohamed Shalaby, Emma Pengelly, Kay Devlin, Benedict Garman, Joshua Cheetham and Alex Murray.

Update: This piece was amended to reflect expert analysis of a blast sound heard in a video.