Together with Nidal Farhat, Masoud manufactured the first Qassam rocket in 2001, which is actively deployed by the Izz ad-Din al-Qassam Brigades against military and civilian targets in southern Israel.
He joined the Izz ad-Din al-Qassam Brigades, Hamas's military wing, and participated in raids against the Israeli Defense Forces in Gaza.
The rocket was first deployed on 26 October 2001, when the Izz ad-Din al-Qassam Brigades claimed credit for launching one from the Gaza Strip into the Israeli city of Sderot.
[2] On 11 June 2003, a Hamas suicide bomber dressed as an Orthodox Jew detonated an explosive device and killed 17 people in Jerusalem.
Approximately half an hour after the bombing, Israeli Apache helicopters fired missiles at Masoud's car in Gaza City, killing him.