Nearly 450 flights were cancelled early morning at the Ngurah Rai airport after Mount Aging shot smoke and ash some 2000 metres  (6500 feet) into the sky.

The shutters on the airport were brought down some early on Friday after a pilot flying overhead found volcanic ash at a height of 23,000 ft.

Ash is perilous for planes as it makes the runway slippery besides damaging the engine.

The main international airport of Bali would remain shut at least till Friday evening and officials also said that two other domestic airports have also been closed.

This might be risky for the lucrative tourism industry in Bali and there might be chaos caused in travel after the Agung erupted in November last year.

According to the National Disaster Mitigation Agency, nearly 4500 flights were cancelled which has affected some 75000 people.

The winds would carry the ash, southwest towards Indonesia's most populated island Java, said officers from the regional Volcanic Ash Advisory centre in Darwin, Australia.

Agung's status remained on high alert and there is a 4km (2.5 mile) no-go-zone around its peak.

Rod Bird, a visitor from Australia had come to the airport only find out that his flight to Perth has been cancelled, for the second time.

He told AFP, "They told us the volcano is going off so they rebooked us for this morning and we got here at 5:00 am only to be turned away again."

He added, "so we’ve had two cancelled flights."

“Well it’s Bali, these things happen and we are fine with it. We just miss the kids."

Bali governor Made Mangku Pastiga calmed the passengers and said that the crater activity had declined since Thursday evening.

He said, "We will try our best to find a solution so all visitors can continue their trip."

It was back in 1963 that the volcano, 70 km away from Bali's famous tourist spot Kura, had erupted which claimed the lives of 1,100 people.

Last year, the volcano saw an increase in activity as a result of which many were evacuated.

Things had quietened in the recent past and officials had lowered it's alert status this year.