- ITV News Correspondent Neil Connery reports
In a disused police station not far from the Saudi border some of the bombs used in Yemen's war lie in storage.
As you walk into the hall the casing of a US cluster weapon sits on the floor. In a room nearby a partly exploded BL-755 British cluster weapon.
Some of its deadly cargo of British bomblets are neatly lined up near the bombs dispensing mechanism.
Amnesty international say it was discovered in a field near the Saudi border in January.
In 2010 the UK agreed to ban these weapons and prevent their use by anyone else.
Ministers say this is an old weapon dropped before the treaty was signed. But Amnesty and other experts argue the evidence suggests it was dropped during the current conflict.
Six days after the British weapon was brought here in April three members of a mine clearance team working at the facility were killed in an explosion.
In the room where they died the debris from the explosion lies strewn across the floor. The two holes which pierced the concrete floor give an idea of the power of the blasts.
Gate guard Hassan Marbrouk says he saw the team who died with the British weapons on the day they were killed.
The American-trained Director of the UN-funded mine clearance group the dead men worked for believes the British weapons killed them.
I ask him if there's any doubt in his mind that the British cluster bombs claimed their lives.
"Yes we are sure that it's caused the deaths of people and our de-miners," Ahmed Alawi, Director of Yemen Executive Mine Action Centre said.
The only people who know for certain what happened that day were all killed in the explosion.
But could there be more British clusters bombs in Yemen?
In Saa'da in the north of the country a Yemeni fighter, who asks not be identified, shows us pictures he took in March of three British cluster bombs he says he found.
"We found the British cluster bombs on the ground in Baqim which is a border village. It was the first time I've seen these weapons. We destroyed them to be safe," he said.
In a village near the frontline on the Saudi border locals tell me they've been targeted by deadly and indiscriminate cluster weapons.
One farmer shows me an American cluster bomblet nestling in the sand next to his feet.
"We can't farm here now because of these. This is death. The shrapnel cuts right through you," he said.
As we talk the roar of the Saudi-led coalition jets in the skies above is a reminder of the ever-present threat.
Farmer Ibrahim Bedidi shows me the injuries he suffered from a cluster bomb after it blew one of his toes off.
The villagers tell me they've put the cluster bombs they've managed to find at the bottom of an empty well.
Along the border cluster bombs from a number of countries pose a deadly threat. But what we've seen and heard during our time here raises further questions for the British government.
- Watch Neil Connery's report in full on ITV News at Ten