There was no immediate comment by Hamas officials of the Interior Ministry, however, dozens of Hamas security men were seen closing streets and stopping and searching cars.

No one has claimed responsibility for placing the bombs.

Two weeks ago, Hamas security forces killed 24 people, including the political and military leaders of a radical Jihadi Salafi (Sunni Moslems) group alled Ansar Jond Allah (Warriors of Gaza) in a mosque in the southern Gaza Strip town of Rafah.

The Al Qaeda inspired group has repeatedly threatened on its website to avenge the deaths of its leaders.