The Palestinian ambassador to Prague was killed in an explosion that was triggered when he opened the door to a safe, Czech police said.
"According to information from the investigation so far, this was definitely not a terrorist attack," national police president Martin Cervicek said on Czech Television.
Police spokeswoman Andrea Zoulova said an explosive - which may have been part of a security mechanism - went off after the safe was opened. "With the greatest probability, an explosive device placed on the door of the safe was triggered," she said.
The Palestinian foreign ministry, in a statement reported by the official WAFA news agency, said the blast happened minutes after Jamal opened a safe that had come from the embassy's old offices.
Some safes can be fitted with small charges to destroy secret documents in the event of the lock being tampered with.
More top news
Stephen Crabb has announced that he is running to be the next leader of the Conservative party.
Rain and cloud will continue to spread eastwards across Wales and England, turning heavy in places.
A sexual predator who groomed murdered teenager Kayleigh Haywood on Facebook has been found guilty of holding her captive at his home.