TRIPOLI, Libya — A group of disgruntled militiamen took over the country’s main airport on Monday, storming it with heavy machine guns and armored vehicles and forcing airport authorities to divert flights, a security official said.

Mohammed el-Gharyani of Tripoli Security Committee said militiamen from the city of Tarhouna occupied the airport runway. Flights were diverted to Metiga air base in the city’s center.

He said the militiamen were angry over arrest of their commander, Abu Elija, on Sunday.

Tunis Air announced Monday that it had canceled two flights to Tripoli in response to the violence and was waiting to see how the situation evolved, the company said in a statement.

Tarhouna in central Libya was widely seen as a favorite of deposed ruler Moammar Gadhafi. Its dominant tribe, also called Tarhouna, held many positions in the Libyan military under Gadhafi. The city’s residents are viewed with suspicion by former rebels.

Tribal rivalries have swept Libya since Gadhafi was overthrown last year. Much of the fighting has pitted militias that fought Gadhafi against those who remained loyal to his regime.