Several flights to and from the Indonesian resort island of Bali have been cancelled or delayed after one of country’s most active volcanoes erupted.

Mount Lewotobi Laki-Laki on the island of Flores spewed an ash tower more than 11 km (6.8mi) into the sky at 17:35 local time (10:35 BST) on Tuesday, the country’s volcanology agency said.

There have not been any reports of casualties. Authorities have raised the highest alert level and advised residents to avoid activities within a 7km radius around the crater.

Air India, Air New Zealand, Jetstar, Juneyao Airlines, Singapore Airlines and Virgin Australia were among those that have cancelled flights to and from Bali, located west of Flores.

Flight data from I Gusti Ngurah Rai International Airport at noon on Wednesday showed that over 20 flights have been cancelled due to the volcano.

Several domestic AirAsia flights leaving for Flores have also been cancelled.

The twin-peaked volcano erupted multiple times in November, killing nine people and forcing thousands to flee.

Geology agency head Muhammad Wafid warned of potential lahar floods – a type of mud or debris flow of volcanic materials – if heavy rain occurs.

Residents were also urged to wear face masks to protect themselves from volcanic ash.

The National Disaster Mitigation Agency said that at least one village had been evacuated, and ash rain was reported in several others outside the exclusion zone.

A spokesman called on residents around the volcano “to evacuate to safe locations” as tremors were still being detected, which indicated ongoing volcanic activity.

Indonesia sits on the Pacific “Ring of Fire” where tectonic plates collide, causing frequent volcanic activity as well as earthquakes.

Lewotobi Laki-laki’s last eruption was in May, when authorities also raised the level to the most severe.

Laki-Laki, which means “man” in Indonesian, is twinned with the calmer but taller 1,703m named Perempuan, the Indonesian word for “woman”.