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UN, June 13 (RIA Novosti) - United Nations Secretary General Ban Ki-moon has launched talks with Palestinian leaders on possible UN intervention in ongoing factional violence in Gaza, his spokesperson said Wednesday.

Israeli Prime Minister Ehud Olmert has urged the UN to send troops into Gaza to end violence between the radical Hamas movement and the pro-presidential Fatah.

At least 17 people were killed and 50 wounded Wednesday when Hamas militants blew up Fatah supporters' headquarters, in the latest attack in war-torn southern Gaza. A total of 67 people have been killed in the region since June 7, when the groups broke a ceasefire signed two weeks earlier.

Spokesperson Michelle Montas said the UN secretary general was alarmed by the developments on the Palestinian territories, but had not yet made a final decision.

Hamas, which seized the security headquarters controlled by the PNA president and Fatah leader Mahmoud Abbas Tuesday, demanded that the group leave Gaza. Fatah leaders ordered the suppression of the "Islamist rebellion", and suspended their membership of a governing coalition with Hamas.

A Fatah source said Wednesday that Hamas militants were close to gaining control of Gaza.

Israel proposes a peacekeeping mission in Gaza on the border with Egypt to prevent arms smuggling into the region.

The UN said in a statement on Tuesday that the latest wave of violence was threatening the PNA coalition government, formed through Arab states' mediation in February.

Ban Ki-moon is expected to discuss the situation with UN Security Council members at an informal closed dinner later Wednesday.