Twenty years after the disbanding of the communist Warsaw Pact alliance, its weapons still kill in Bulgaria as lack of money and suspected corruption hinder the dismantling of tons of old munitions.

Three workers were killed and nine others injured last week in a series of explosions at an arms dismantling depot belonging to private company Bereta Trading, near the village of Lozenets in eastern Bulgaria.

The initial violent blast, which left a crater four to six metres (13 to 20 feet) deep, was probably due to a violation of safety regulations, prosecutors said.

The scale of the accident could have been limited if the company had not kept stocks of other munitions in the arms dismantling warehouse, deputy chief prosecutor Boyko Naydenov explained.

Survivors from the blasts -- all poor men from nearby villages -- told television crews that they were given for days training and paid 300 leva (150 euros, $187), barely above the minimum monthly wage of 290 leva, to do the dismantling.

"It is not that Bereta Trading could not hire professionals. It preferred to save on salaries," Trud newspaper commented after the explosions.

It noted that many specialists who were laid off from the arms industry after it was crippled following the fall of communism in 1989 were available to do the work.

"It is ridiculous to train people for four days to destroy explosives," security expert Ivan Boyadzhiev commented on state BNT television.

Iren Kostova, whose husband did not return from work after the explosion and is feared dead -- none of the bodies were found -- slammed the company's owner for the damages he said would pay.

"He evaluated my husband's life at 1,000 leva!" Kostova told private bTV television.

The injured men were promised half this sum.

Meanwhile, Bereta Trading reportedly paid for a 3,200-euro trip to Bali by a defence ministry official who played a key role in granting permits to the company, according to Bulgarian media.

"Corruption explodes and kills," Trud titled an article about the lucrative arms dismantling trade.

It cited a businessman from the sector who said his minimum annual profit amounted to 300 percent of his costs.

"It is only normal for these projectiles, mines and grenades to be destroyed by specialists. But this is not the case when big bucks are involved," the newspaper added.

Bulgaria had a 150,000-strong conscript army during communism that could reach up to 400,000 if reservists were called in, but this has now fallen to a professional force of just 30,000.

The shrinking in ranks landed Bulgaria with huge amounts of excess arms and munitions, which had to be stored somewhere while awaiting the necessary money for destruction.

As years went by, accidents started to multiply.

The first major one was in July 2008 when 20,000 tons of munitions exploded at an army depot just outside Sofia.

No one was killed, causing the media to speculate that the explosion may have been sparked deliberately to cover up large-scale theft at the depot.

Afterwards, the ministry of defence tasked private companies with destroying the remaining 43,500 tonnes of old munitions at 12 depots around the country. The law excluded foreign companies from the process.

Other accidents continued to occur but without major injuries.

The massive blasts last week, which rained shells all over a key highway intersection east of the capital, temporarily shutting it, fed the doubts about the capacity of Bulgarian companies to manage the job.

Defence Minister Anyu Angelov said he was considering changing the law in order to let EU companies step in to finish dismantling the remaining 15,000 tonnes.

However, feeble controls in the arms sector were highlighted again on Friday when police found 103 rockets in a minivan and believed them stolen, due to irregular paperwork.

The manufacturer, state arms giant VMZ Sopot, said it was just a routine transport.