Bull concurrently worked on the Scud project, making calculations for the new nose cone needed for the greater re-entry speeds and temperatures the missile would face.
Over a period of a few months following, his apartment suffered several non-robbery break-ins, apparently as a threat or a warning, but he continued to work on the project.
In March 1990, he was assassinated.
One account states he was shot five times in the head and back at point blank range while approaching the door of his apartment in Brussels.
Another account states he was shot by a three-man team on March 20, 1990, when he answered the doorbell.

The co-operation between Bull and Saddam Hussein was an immediate threat to Iran and Israel, as Iran had endured an eight-year-long war with Iraq, and Israel had previous military engagements with Iraq during the Arab–Israeli war.
Watching development of the gun, Israel feared it could be used to launch nuclear weapons, but the re-designed Scud missiles were of greater concern at that moment.
As for Iran, it was under threat from both Bull's supergun and his re-designed Scud missiles.

According to investigative journalist Gordon Thomas, the assassination of Bull had been sanctioned by Israeli Prime Minister Yitzhak Shamir.
Nahum Admoni sent a three-man team to Brussels, where the Mossad agents shot Bull at his door-step.
Within hours of the killing, according to Thomas, Mossad was engaged in distributing false stories to the European media, alleging that Bull had been shot by agents from Iraq.

Although it was in the immediate interest of both Israel and Iran that Bull discontinue his co-operation with Saddam Hussein, he had worked for many different parties in many critical defence projects, and had become both an asset and a liability for several powerful groups simultaneously.
Due to Bull's past ventures, it has been speculated that besides Iran or Israel, the CIA, MI6, or the Chilean, Syrian, Iraqi, or South African government could have been behind his assassination.

Project Babylon was stopped when supergun parts were seized by Customs in the United Kingdom in November 1990, and most of Bull's staff returned to Canada.
The smaller test gun was later broken up after the Persian Gulf War.

Bull's assassination and the supergun are central plot elements in Louise Penny's 2015 novel The Nature of the Beast.
Bull concurrently worked on the Scud project, making calculations for the new nose cone needed for the greater re-entry speeds and temperatures the missile would face. Over a period of a few months following, his apartment suffered several non-robbery break-ins, apparently as a threat or a warning, but he continued to work on the project. In March 1990, he was assassinated. One account states he was shot five times in the head and back at point blank range while approaching the door of his apartment in Brussels. Another account states he was shot by a three-man team on March 20, 1990, when he answered the doorbell.
The co-operation between Bull and Saddam Hussein was an immediate threat to Iran and Israel, as Iran had endured an eight-year-long war with Iraq, and Israel had previous military engagements with Iraq during the Arab–Israeli war. Watching development of the gun, Israel feared it could be used to launch nuclear weapons, but the re-designed Scud missiles were of greater concern at that moment. As for Iran, it was under threat from both Bull's supergun and his re-designed Scud missiles.
According to investigative journalist Gordon Thomas, the assassination of Bull had been sanctioned by Israeli Prime Minister Yitzhak Shamir. Nahum Admoni sent a three-man team to Brussels, where the Mossad agents shot Bull at his door-step. Within hours of the killing, according to Thomas, Mossad was engaged in distributing false stories to the European media, alleging that Bull had been shot by agents from Iraq.
Although it was in the immediate interest of both Israel and Iran that Bull discontinue his co-operation with Saddam Hussein, he had worked for many different parties in many critical defence projects, and had become both an asset and a liability for several powerful groups simultaneously. Due to Bull's past ventures, it has been speculated that besides Iran or Israel, the CIA, MI6, or the Chilean, Syrian, Iraqi, or South African government could have been behind his assassination.
Project Babylon was stopped when supergun parts were seized by Customs in the United Kingdom in November 1990, and most of Bull's staff returned to Canada. The smaller test gun was later broken up after the Persian Gulf War.
Bull's assassination and the supergun are central plot elements in Louise Penny's 2015 novel The Nature of the Beast.
Gerald Bull