The Thai Embassy in Indonesia has warned its nationals to avoid the area near the rumbling Mount Sinabung volcano on Sumatra island that has sent a massive column of ash and smoke about 5,000 metres into the air.
In a post on its Facebook page, the embassy said there were no reports of Thais having been affected by the incident.
In case of emergency, Thais could contact the Honorary Thai Consulate General office in Medan at (+62) 813 708 88785 or call the Embassy's emergency telephone number (+62) 811 186253 around the clock.
The Indonesian authorities have issued a ban on people entering an area within a radius of seven kilometres of the volcano.
Mount Sinabung volcano erupted Monday, leaving local villages coated in debris and officials scrambling to hand out facemasks to residents.
The volcano has been rumbling since 2010 and saw a deadly eruption in 2016. It spewed a thick plume of ash after activity picked up recent days.
The Jakarta Post on Monday quoted Centre for Volcanology chief Kasbani as saying this was the biggest eruption for Sinabung this year.
There were no reports of injuries or deaths.
No one lives inside a previously announced nogo zone around the volcano.
But hundreds of houses outside the sevenkilometre danger zone were covered in volcanic ash.
Officials have distributed facemasks and urged local residents to stay indoors to avoid respiratory problems, said local disaster mitigation agency official Nata Nail Peranginangin.
“In some villages the visibility was barely five metres after the eruption – it was pitch black,” Peranginangin added.
Pressure inside the crater was threatening to spark collapses in its dome, the official said.
Sinabung roared back to life in 2010 for the first time in 400 years. After another period of inactivity, it erupted once more in 2013 and has remained highly active since.
In 2016, seven people died in one of Sinabung's eruptions, while a 2014 eruption left 16 people dead.
Indonesia is home to around 130 volcanoes due to its position on the “Ring of Fire”, a belt of tectonic plate boundaries circling the Pacific Ocean where frequent seismic activity occurs.