Jimmy McGovern in the line of fire over Afghanistan drama

He made his name creating gritty characters, tough men grafting under pressure and battling against the odds. Now it is Jimmy McGovern, the plain-talking screenwriter behind dramas like Cracker and The Street, who has been forced into the firing line.

The Bafta-winning writer has been forced to defend an episode of his latest drama, Accused, which follows the consequences of two friends who join the Army and disobey orders while serving in Afghanistan.

The programme was criticised yesterday by a senior Army veteran as being "irresponsible" and "desperate to shock". Colonel Tim Collins, who famously gave a rousing address to his troops on the eve of the Iraq war, said the programme, which airs next Monday on BBC1, "abjectly fails" the "responsibility test" and "fails the soldiers on the front line".

The episode is part of McGovern's Accused series, which explores six different tales of crime and punishment. But the second installment in the series has angered Colonel Collins, who told the Radio Times that the drama was full of "gratuitous violence".

He described the programme, which stars Mackenzie Crook and newcomers Ben Smith and Ben Batt, as containing "non-commissioned officers [running] a camp that has more in common with Second World War Japan than modern-day Afghanistan". Colonel Collins retired from the Army in 2004.

"The constant and slightly contrived use of foul and abusive language and the generous lashings of gratuitous violence all add up to a desperate plea to be seen as shocking and cutting edge," he said.

"The actors don't seem convinced of the whole proposition. And I don't blame them. Having served in the British Army for 23 years I can unequivocally say that this has absolutely no basis in reality."

He continued: "There is no point to Accused except to try to shock. But my worry is that the parents and partners of soldiers serving in Afghanistan will regard this as in some way believable. At this very moment we have men laying down their lives in Afghanistan so that Jimmy McGovern retains his freedom to attack them."

In a statement issued yesterday, McGovern responded: "This episode is a work of fiction and as a dramatist I was interested in exploring how soldiers have to be at a certain mindset to kill. It is not my intention to slur British soldiers, for whom I have the greatest respect. At the heart of the drama is my belief in the sanctity of life."

Last week, the writer revealed that his acclaimed BBC1 drama The Street had come under fire from the BBC's compliance unit because corporation watchdogs felt some scenes could cause offence to Manchester United fans.

"I told them every chance I get I write with anti-Manchester United bias," he said. "I'm a dramatist. Imagine on my tombstone if it read 'Jimmy McGovern, writer – never offended anybody'. How would I feel? That's my job."

The BBC denied McGovern's claim.