(CNN) -- Syria's Ministry of Interior set up a committee to investigate Friday's deadly demonstrations in Diraa, the Syrian news agency SANA reported Saturday.
Anyone who is proven responsible for having committed abuse during the protests will be punished, the news agency reported, citing an unnamed source.
Meanwhile, during the funeral Saturday for two people reportedly killed during the clashes in Diraa, hundreds of people gathered to call for freedom and reforms.
"The general atmosphere was tense," one participant told CNN, referring to demonstrators and security forces, "but no serious clashes occurred."
Said another participant: "None of the slogans were against the president, but all are asking for more freedom and putting an end to the current corruption."
The United Kingdom's Foreign Office Minister for the Middle East Alistair Burt said Saturday that he was "extremely concerned by reports of increasing violence and the excessive use of force by security forces, apparently resulting in the death of a number of protesters yesterday."
"I am also disturbed by reports of the arrest and prosecution of around 20 human rights activists who attempted to conduct a peaceful protest outside the Interior Ministry on Wednesday," Burt said. "This, along with reports of demonstrations in towns around Syria being broken up with lethal force is very worrying.
"I call on the government of Syria to respect the people's right to peaceful protest and listen to their legitimate grievances," he added. "I welcome the news that the Syrian authorities are planning an investigation into the deaths of protesters yesterday. This process needs to be a fair and transparent and ensures that those responsible are held accountable."
The funerals came a day after United Nations Secretary-General Ban Ki-moon called the use of lethal force against peaceful demonstrators in Syria "unacceptable."
Ban said in a statement that he is "concerned about the reported killing of demonstrators" in Diraa on Friday.
Witnesses said riots erupted Friday in the Middle Eastern nation. It is the latest of a string of Arabic-speaking nations beset with discontent.
The unrest spread through Hims, Diraa, Banyaas, Der Elzour and the capital, Damascus, witnesses said, and there were claims of deaths and injuries, but the assertions could not be independently confirmed.
Calling it "the responsibility of the government to listen to the legitimate aspirations of the people," Ban urged Syrian authorities to refrain from violence and to abide by their international commitments regarding human rights, which guarantee the freedom of opinion and expression, including the freedom of the press and the right to peaceful assembly.
His comments were echoed Friday by the United States, which urged the Syrian government to "address the legitimate aspirations" of its people.
"The United States strongly condemns the violence that has taken place in Syria today and calls on the Syrian government to allow demonstrations to take place peacefully. Those responsible for today's violence must be held accountable," said U.S. National Security Council spokesman Tommy Vietor.
Demonstrators took to the streets Friday to demand freedom and urge an end to corruption, but police surrounded hundreds of them and made arrests.
"Security forces are clearly nervous and did not expect to have demonstrations in five different places at the same time," a witness said.
A Facebook page that called for "Dignity Friday" showed images of clashes between protesters and security personnel.
CNN's Caroline Faraj contributed to this report.