DUSHANBE, February 21, 2011, Asia-Plus  -- Colonel Muammar Gaddafi''s regime is under pressure amid unprecedented protests in the Libyan capital and defections by senior diplomats, according to BBC.

Protesters out on the streets of Tripoli late on Sunday were met by security forces using live ammunition and tear gas.

Benghazi, the country''s second city, now appears to be largely under the control of protesters, BBC reports.

But Colonel Gaddafi''s son, Saif al-Islam, has warned that civil war could ignite.  In a lengthy TV address, he offered significant political reforms but also vowed that the regime would "fight to the last bullet" against "seditious elements".

According to Al Jazeera television broadcaster, Gaddafi said his father remains in the country and is backed by the army, despite reports from several cities that soldiers have refused to take action against protesters and in several cases have joined their ranks or withdrawn.

Following Saif Gaddafi''s speech, witnesses in Tripoli reported an escalation of violence, as supporters of his father flooded into the city''s central square and confronted anti-government protesters.  Al Jazeera, citing medical resources, reported that 61 Libyans were killed in Tripoli clashes.

Libya''s envoy to the Arab League, Abdel Moneim al-Honi, announced he was "joining the revolution" and its ambassador to India, Ali al-Essawi, told the BBC he was resigning in protest against his government''s violent crackdown on demonstrators, BBC reported.

Mohamed Bayou, who until a month ago was chief spokesman for the Libyan government, said the leadership was wrong to threaten violence against its opponents.  He made his comments in a statement obtained by the Reuters news agency which appeared to indicate disagreement within the ruling elite.

In another blow to Colonel Gaddafi''s rule, two tribes - including Libya''s largest tribe, the Warfla - have backed the protesters.

Human Rights Watch says at least 233 people have died since last Thursday, though in his speech, Saif Gaddafi insisted reports of the death toll had been exaggerated.

The US, UK and French governments are among those which have condemned the harsh treatment of protesters.