JAKARTA, Indonesia – Eruptions at two volcanoes Thursday caused closures at three Indonesian airports, including one serving the country’s second-largest city.

Mount Raung on the main island of Java blasted ash and debris up to 2,000 metres (6,560 feet) into the air after rumbling for several weeks, and Gamalama mountain in eastern Indonesia erupted Thursday morning after months of quiet.

Transport Ministry spokesman Julius Adravida Barata said volcanic ash spewing from Raung blew close to the cities of Surabaya and Malang, forcing Juanda International and Abdurrahman Saleh airports to close.

Surabaya, the provincial capital of East Java, is Indonesia’s second-largest city after the capital Jakarta.

The ministry said Sultan Babullah airport in Ternate, North Maluku’s province capital, was closed after Gamalama sent volcanic ash as high as 1,500 metres (4,920 feet) into the sky.

The shutdown came at the peak of the annual exodus of millions of people to their hometowns in the world’s most populous Muslim nation coinciding with the celebration of the end of the holy fasting month of Ramadan.

An earlier eruption of Raung last week sparked chaos as Ngurah Rai airport in the tourist hotspot of Bali and four other airports in the region were shutdown, stranding thousands of holiday-goers.

Two domestic airports in East Java towns of Banyuwangi and Jember have been closed since then.

Volcanic ash is hazardous to jet engines and able to harm other parts of the aircraft.

A 2010 eruption of Iceland’s Eyjafjallajokul volcano produced an ash cloud that caused a week of international aviation chaos, with more than 100,000 flights cancelled.