BEIRUT -- Activists say Syrian security forces have opened fire on protesters in three different parts of the country, killing at least seven.

The London-based Syrian Observatory for Human Rights and a second activist group, the Local Coordination Committees, both reported one person killed in the Damascus suburb of Saqba and another killed in the northern village of Andan on Friday.

The observatory said seven people were also killed in the southern village of Dael, while the coordination committees put the death toll there at five.

Thousands protested throughout Syria Friday calling for the downfall of President Bashar Assad.

The U.N. estimates that over 3,000 people have been killed in Syria's seven-month uprising and the ensuing government crackdown.