BEIRUT — Syrian rebels have captured a hydroelectric dam on the Euphrates river in the country's north in a strategic victory that followed days of fighting, activists said.

The Britain-based Syrian Observatory for Human Rights says the Tishrin Dam, near the town of Manbij, fell to the rebels before dawn on Monday.

Rami Abdul-Rahman, who heads the Observatory, says the dam supplies several areas of Syria with electricity.

The rebels have been making strategic advances recently. On Sunday, they briefly captured a regime helicopter base outside Damascus.

Also Monday, Syrian war planes attacked a rebel headquarters near the Turkish border but appeared to miss their target, opposition activists said.

"The [Free Syrian Army] joint command is located in a school. It seems they have missed it. There were two jets — one of them looked like a reconnaissance aircraft. They had been flying over the area for an hour," activist Mohammad Abdallah told Reuters.

They said a Turkish fighter was scrambled to the area. There was no immediate comment from Turkish authorities about the incident, which occurred in Atima village in hilly farmland across the border from Turkey's Hatay province.

Rebels fired anti-aircraft guns at the jets but they were flying too high to be hit, they said.

Turkey has requested that NATO surface-to-air missiles be stationed on its side of the border, angering Syria, but said on Monday they would only be used to protect Turkish territory and not to establish a no-fly zone.

Syrian jets have bombed rebel targets along the frontier but Monday's strike was one of the closest to the border, just 1.5 miles from a Turkish police compound and near a crossing point for Syrian refugees.

Another activist described how the planes were circling the area when they struck. The sound of what appeared to be rockets and explosions could be heard over the phone.

"They fired three rockets. It looks like that they hit nearby buildings. There are no reported casualties. It seems that the Free Syrian Army was expecting the air strike and had evacuated the area," he said.

Syria's conflict started in March 2011 as uprising against President Bashar Assad's regime, inspired by other Arab Spring revolts. It quickly morphed into a civil war that has since killed more than 40,000 people, according to activists.

Information from The Associated Press and Reuters was used in this report.