The Palestinian ambassador in Prague was holding explosives in his hands when he died in a bomb blast at his official residence in January, say the Czech police.

According to Prague police spokeswoman Andrea Zoulova, the Czech authorities conducted ballistics tests which demonstrated that the bomb material was being held by ambassasdor Jamal al-Jamal’s at the time of the explosion.

Previously it was unclear whether the explosives had detonated while inside the ambassador's safe or if they were triggered by a booby-trap style device.

"The explosive was not placed on the door or inside the safe and was not there to protect the safe," said Ms Zoulova speaking to the AFP news agency. But she stressed the investigation was ongoing.