A POLICE officer's trip to the US went with a bang when he took part in a specialist training exercise.

Arson investigation expert Detective Constable Graham Thompson, of Cleveland Police, built a bomb, detonated it and collected the remains for forensic testing.

He spent two weeks at the Bureau of Alcohol, Tobacco and Firearms (ATF) training complex, in the foothills of the Blue Ridge mountains, Virginia.

But before he was let loose with explosives, he spent a week at the ATF headquarters in Washington getting an insight into how Americans tackle arson and explosives training.

DC Thompson joined 33 officers from all over the US on the course, where they assembled a bomb hidden inside a bag.

The explosive was armed with two sticks of gelignite and triggered with a trip switch to explode as soon as it was picked up.

When it was detonated, the investigators collected the forensic evidence and searched for clues - just as in a real incident.

His three-week trip also saw him spend time with the head of the Arson and Bomb National response team - the same people who dealt with the September 11 attack on the World Trade Centre - and an official attached to the FBI psychology profiling unit at Quantico.

"I was the first UK police officer to attend the course, which dealt with everything from the profile of a bomber, the chemistry of explosives to actually making a bomb, blowing it up and the forensic recovery of the aftermath.

"The course was extensive and thought-provoking. I am now looking forward to passing on the information and knowledge I have gained on the course to Cleveland police and fire brigade officers."

The invite to the course came as a result of the International Fire and Arson Conference, organised by Cleveland Police this year.