Hussein al-Mabhouh, brother of top Islamic Hamas movement militant Mahmoud al-Mabhouh, said on Friday that Mossad, Israel's security intelligence service, was behind the killing of his brother in Dubai.

Al-Mabhouh told reporters near his house in Jabalia refugee camp in northern Gaza Strip that Mossad "killed my brother Mahmoud by electric shock at his head after putting pieces of cloth over his nose and mouth in Dubai."

He said that his brother, who arrived in Dubai on Jan. 19 on a secret Hamas mission, was found dead the next day.

"We were not surprised when it came to our knowledge that Mahmoud was killed. Mossad had tried twice to kill him. The first time was in 1989, and the second was in Beirut six months ago," said Hussein al-Mabhouh.

Earlier in the day, Islamic Hamas movement and its armed wing al-Qassam Brigades, also accused the Israeli security intelligence of killing Mahmoud al-Mabhouh in Dubai.

Izzat al-Resheq, Islamic Hamas movement politburo member, told a Hamas news website on Friday that Israel was behind the killing of Mahmoud al-Mabhouh in Dubai on Jan. 20.

Al-Mabhouh is one of the founders of Hamas's armed wing, known as Izzedein al-Qassam Brigades, at the beginning of the first Palestinian Intifada, or uprising, in 1988.

Israel accused him of being behind the kidnapping and killing of two Israeli soldiers in Gaza in 1988. Most of those involved in the incident were either detained or killed by Israel, including Hamas founder and spiritual leader Sheikh Ahmed Yassin, who was killed in 2004.

Since he fled the Gaza Strip in 1988, Mahmoud al-Mabhouh has been living abroad, mainly in Damascus.

Meanwhile, al-Qassam Brigades in Gaza said in a leaflet sent to reporters that it mourns al-Mabhouh's death and vowed to revenge his assassination.