CAIRO, Egypt (AP) _ The engineer who supervised construction of a ``super gun'' for Iraqi leader Saddam Hussein's artillery has defected and is seeking asylum in Germany, Iraqi dissidents said Monday.

Nizar al-Qaseer, who also served as irrigation minister until he was sacked last year, slipped into Kurdish-controlled northern Iraq and sought the help of Kurdish rebels, the dissidents said.

They said al-Qaseer, who is accompanied by his family, wants to go to Germany, where he studied engineering.

The dissidents, who live in Jordan, spoke on condition of anonymity.

Meanwhile, an Iraqi opposition group claimed three of its members were killed Thursday when their plot to assassinate Saddam was uncovered.

Their plot was uncovered minutes before the men were to board a helicopter to the Habaniya resort, where they planned to attack Saddam, the National Democratic Trend said in a statement faxed to The Associated Press.

The men, all members of the air force, were killed by Iraqi security, the statement said. It identified them as Maj. Fawzi Karim Al-Hamadani, Capt. Hussam Aldin Khalaf Al-Assadi and Abdellah Ghaidan, a non-commissioned officer.

The report could not be confirmed independently.

Both Iraqi opposition groups and Israeli media recently have reported the executions of dozens of army officers after what they said was a failed coup attempt in June. Several air force officers also were arrested, opposition groups said.

The latest defection follows the March departure from Iraq of Gen. Nizar al-Khazraji, a former chief of staff of the Iraqi army. Al-Khazraji directed the armed forces during the final three years of the 1980-88 Iran-Iraq war and was one of the highest ranked officers ever to defect from Saddam's regime. He defected to Jordan.

Al-Qaseer was the top aide to Gen. Hussein Kamel Al-Majid, Saddam's son-in-law who was responsible for Iraq's military-industrial complex. Al-Majid and his brother defected to Jordan in August 1995, but returned to Baghdad in February and were killed.

After al-Majid's defection, al-Qaseer was relieved of his ministry job and moved to the ceremonial post of presidential adviser.

The dissidents said al-Qaseer had been in charge of Iraq's ambitious program to build a huge artillery piece known as the ``super gun'' before the scheme was uncovered in the aftermath of the 1991 Gulf War.