Two bombs went off near a mosque and inside Gaza's main security compound early on Sunday in the latest violence to shake the troubled coastal territory, security officials said. No injuries were reported.
The explosions appeared to be revenge attacks against Gaza's rulers, the Islamic militant group Hamas. Officials said they defused two more bombs hidden in the Ansar compound in Gaza City. They spoke on condition of anonymity because they were not allowed to speak to reporters.
There were no immediate claims of responsibility. However, a shadowy group loyal to al-Qaida called Jund Ansar Allah -- Soldiers of the Companions of God -- has sworn to attack Hamas security compounds and mosques in retaliation for a deadly shootout earlier this month.
Twenty-eight people died a gunbattle between Hamas police and the group that took place in and around a mosque in the southern Gaza Strip town of Rafah two weeks ago. The battle began after the group's spiritual father announced he would establish an Islamic emirate in Gaza.
Hamas interior ministry spokesman Ihab Ghussein said they were investigating the explosions. Also today, an Israeli aircraft bombed a tunnel in the northern Gaza Strip that military officials said could be used by militants to infiltrate Israel.
A military spokeswoman said the tunnel was being dug about a mile from Gaza's border with Israel by organisations not connected to Hamas.