DAMASCUS (AFP/Reuters) - Syria sent more troops to the southern town of Daraa on Tuesday where a deadly crackdown against pro-democracy protesters raged into a second day, activists said, as Washington considered targeted sanctions against Damascus. Britain said it was working with Western partners to send a strong signal to Damascus, while France and Italy denounced the unacceptable situation in Syria. Washington ordered non-essential embassy staff to leave Syria which has been shaken by six weeks of protests against President Bashar al-Assads autocratic rule and Italy warned its citizens against travel there. And UN rights chief Navi Pillay, who has denounced the disregard for human life in Syria, has been invited to visit Damascus, a spokesman said, urging authorities to probe the killing of protesters. Nearly 400 people have been killed by security forces firing live rounds and tear gas since March 15, activists say, including 25 on Monday alone in Daraa, with scores of arrests. New army troops and security reinforcements have entered Daraa and a tank was deployed in the central Kaziat al-Balad square, activist Abdullah Abazid told AFP by telephone from Daraa near the Jordanian border. He said troops were firing on residents and a mosque and had laid siege to the home of Daraas top Muslim cleric, Mufti Rizk Abdulrahman Abazeid, who quit last week in protest at the crackdown. The bullets continue against the people, but we are resisting, he said, adding that shooting continued well into the afternoon. The Abu Bakr Assidiq mosque, schools and reservoirs were hit and shops looted, Abazid said, adding that tanks and roadblocks are deployed at the entrance to the town, preventing anyone from entering. Residents complained that water and electricity had been cut throughout Daraa since dawn on Monday, when 3,000-5,000 Syrian troops backed by tanks and snipers rolled in. Abazid said communications were also down. Also on Tuesday, authorities referred to military court prominent dissident Mahmud Issa owning a satellite phone, a week after his arrest and an interview he gave to Al-Jazeera television, a leading activist said. Mahmud Issa will be tried by a military court for owning a Thuraya phone and a high-tech computer, said Rami Abdel Rahman of the Syrian Observatory for Human Rights. Issa was twice jailed in Syria for a total of 11 years. Abdel Rahman said activist Qassem Azzawi was arrested on Tuesday for taking part in an anti-regime protest last week, and that 43 people were rounded up since Monday in raids across the country while 11 others were freed on Tuesday. Activists on Monday said that at least 25 people were killed in day one of the Daraa assault and Abazid said the bodies of 22 people had been retrieved. Amnesty International said tanks shelled civilian buildings in Daraa, commenting: The Syrian governments brutal reaction to its peoples demand for change has reached a new and outrageous low. The operation in Daraa came four days after Assad scrapped nearly five decades of draconian emergency rule and abolished the repressive state security court to pacify protesters demanding reforms and the fall of the regime. Around 160 people have been killed since Thursday, activists and rights group have said. The Syrian army said the troops entered Daraa in response to calls for help from citizens to rid them of extremist terrorist groups behind a spate of killings and sabotage. A huge crackdown was also reported on Monday in Douma, a large suburb in northern Damascus, and nearby Al-Maadamiyeh, said activists and residents reached by telephone. By Tuesday afternoon Douma had become a ghost town and the presence of security forces decreased, one resident told AFP. A witness said three doctors were arrested on Tuesday from the suburbs Hamdan hospital and security forces made patients leave the facility, even those in intensive care. Washington ordered the evacuation of non-essential embassy staff from Syria, where the first US ambassador in six years took his post just three months ago. The United States last week urged its citizens to leave, and the Philippines on Tuesday urged its 17,000 citizens in Syria to leave also. Italy warned its citizens against going to Syria and told those already there to avoid protests. Washington is also considering imposing targeted sanctions against Damascus, National Security Council spokesman Tommy Vietor said on Monday. Britain, Italy and France denounced the violent repression in Syria as British Foreign Secretary William Hague said London was working with the United Nations and European Union to send a strong signal to Damascus. France called for strong measures against Syria, a foreign ministry spokeswoman said as President Nicolas Sarkozy branded the situation in Syria unacceptable, insisting however that France would not intervene without a UN Security Council resolution. Turkish Prime Minister Recep Tayyip Erdogan, who has close ties with Assad, called him on Tuesday to press for reform, an aide said. Diplomats said on Monday that Britain, France, Germany and Portugal are seeking a UN Security Council condemnation of the killing of hundreds of demonstrators in Syria and a call for an independent investigation. Meanwhile Rupert Colville, a spokesman for the UNs Pillay, said she had been invited to Damascus: We look forward to being able to visit and independently assess the situation on the ground, he said. More than 2,000 Syrian security police deployed in the Damascus suburb of Douma on Tuesday, manning road blocks and checking the identity of residents, a witness told Reuters. The witness said he saw several dark green trucks in the streets equipped with heavy machineguns. He said men who he believed were members of the plain clothes secret police were carrying assault rifles. Bus loads of soldiers in full combat gear also crossed the main gate of Douma and began deploying in the suburb, he said. European governments urged Syria on Tuesday to end violence after President Bashar al-Assad sent tanks to crush a revolt against his 11-year rule in the city of Deraa.