Palestinians killed in Gaza blast
Smoke rises at scene of blast in Jabaliya refugee camp
The truck was surrounded by people when the blast happened
At least 10 Palestinians have been killed and scores injured in a blast during a parade by the militant Hamas group in the Gaza Strip, reports say.
Witnesses said a truck carrying gunmen and home-made weapons blew up during the rally in the Jabaliya refugee camp in northern Gaza.
Hamas has blamed Israel, but Israel has denied any involvement.
It is the deadliest incident in Gaza since Israel pulled its troops and settlers out earlier this month.
Hours earlier, Palestinians fired rockets into Israel from Gaza after Israel killed three militants in a raid in the West Bank town of Tulkarm.
The rockets did not cause any casualties.
'People in pieces'
Palestinian witnesses said a crowd, including many children, swarmed round the truck moments before the explosion.
Map showing northern Gaza refugee camp of Jabaliya
Video filmed during the rally showed a large cloud of white smoke rising into the sky, as hundreds of people ran from the scene of the blast.
The pictures also show several badly injured bodies on the ground.
"There was smoke all over, and then we saw people in pieces, but we couldn't make out what really happened," eyewitness Hazem Abu Rashad was quoted by the Associated Press news agency as saying.
The agency quoted another man, who gave his name as Hussam, as saying he helped pull three men out of the truck, two dead and one alive but with a severed leg.
Earlier, Islamic jihad militants fired a volley of rockets into Israel in what they said was retaliation after Israel killed three militants in Tulkarm.
Israel said the militants were killed after opening fire on troops who were trying to arrest them.
The BBC's James Reynolds in Jerusalem says the latest incidents are a sign of high tension in the Gaza Strip even after the Israeli withdrawal.