U.N. Secretary-General Ban Ki-moon has told Syrian President Bashar al-Assad that he is alarmed at reports of excessive use of force by government security forces against citizens and continued widespread violations of human rights.

Mr. Ban spoke by telephone Wednesday with Mr. Assad, who said military and police operations had stopped.

A spokesman for the U.N. chief said Mr. Ban also continued his calls for an independent investigation into the violence, and for Syria to cooperate with the U.N.'s human rights office.

The U.N. Security Council is set to hear Thursday from U.N. human rights chief Navi Pillay, who is expected to call for the Council to refer Syria to the International Criminal Court.

Mr. Ban's spokesman said Mr. Assad also pledged to carry out several reforms in the coming months, including revising the country's constitution and holding parliamentary elections.

Meanwhile, activists say Syrian security forces have detained hundreds of people in the besieged port city of Latakia, filling a sports stadium because local detention centers were overflowing with prisoners.

A London-based Syrian rights group said Wednesday that more than 700 troops raided homes in Latakia's southern al-Raml district, arresting people on lists.

Activists also said forces loyal to Mr. Assad killed nine people in the central city of Homs, including two protesters shot dead in front of a mosque after nightly Ramadan prayers.

Latakia's al-Raml is home to a crowded Palestinian refugee camp where many low-income Syrians also live. United Nations officials say as many as 10,000 residents fled the neighborhood during Syria's four-day operation to crush dissent in the city.

The United Nations Relief and Works Agency said Wednesday it has determined the whereabouts of about 2,000 of the displaced people and is providing them with aid.

At least 35 people have been killed in the Latakia crackdown. Syria announced Tuesday it is pulling its military out of the city and that it has also begun to withdraw forces from the eastern town of Deir el-Zour. However, residents said Wednesday that troops remain in the city.

In the capital, Damascus, troops carried out dawn raids in the predominantly Kurdish neighborhood of Rukneddine, where security forces detained dozens after cutting off electricity. A number of anti-government protests had recently taken place in the neighborhood.

Mr. Assad has been facing growing international pressure to end the violent crackdown.

Turkish Prime Minister Recep Tayyip Erdogan Wednesday compared the situation in Syria with that in Libya, noting that Mr. Assad's government continues to kill civilians despite repeated diplomatic intervention. Separately, Turkish Foreign Minister Ahmet Davutoglu called for “the bloodshed” to stop during a joint news conference with his Jordanian counterpart.

Meanwhile, the United Nations said it is withdrawing its non-essential personnel from Syria.

Rights groups and activists say at least 1,800 civilians have been killed since the start of the government's crackdown in mid-March.