Fatah supporters and Hamas members also exchanged gunfire near the Foreign Ministry today.
Also today, Abbas met with visiting British Prime Minister Tony Blair. The Palestinian leader repeated he would go ahead with plans to hold early elections, despite Hamas objections.
Hamas won a majority in parliamentary elections earlier this year. Since then Fatah and Hamas politicians have been unable to form a unity government.
In other news, Israeli Prime Minister Ehud Olmert said today he supported Abbas's plan to hold early presidential and parliamentary elections.
Olmert added that he hoped to meet with Abbas very soon and that he planned to set up a committee with the Palestinians in the near future to discuss the issue of Palestinian prisoners being held by Israel.
(AP, Reuters, AFP)