Image copyright Sri Lankan police Image caption Pidurangala Rock, seen here in the foreground, is considered sacred by Buddhists

Sri Lankan police have arrested three men who were among a group who took semi-nude photos of themselves at an ancient sacred site.

The young Sri Lankan men posted the images of themselves at Pidurangala Rock on Facebook.

It prompted an angry reaction from people who considered them a religious insult, reports BBC Sinhala's Azzam Ameen in Colombo.

Similar photos were posted on Instagram by foreigners, who were not arrested.

The arrests follow a complaint by a Buddhist monk who claims the photos, taken within sight of the Sigiriya rock fortress, a Unesco World Heritage site, are a religious insult.

Image copyright Sri Lankan police Image caption Seven men also posed semi-naked near Pidurangala Rock

Sri Lanka's Prime Minister Ranil Wickremesinghe also ordered police to carry out an investigation, Sri Lanka's Daily Mirror newspaper reported.

'Brown bums'

The viral photos taken by foreign travellers were posted on the Cheeky Exploits Instagram page, an account that encourages people to take pictures at famous locations around the world.

While many have commended the police for taking action for insulting a religious place, others have criticised it.

"When our children are being raped and women being abused, Sri Lankan police do nothing. They only seem to act on nonsensical non-issues like this," a Facebook user said.

Others questioned why police only took action against locals, not foreigners.

"So law enforcement should only be limited to brown bums? Sri Lanka Police should send several teams around the world to identify the rest," wrote another Facebook user.

This is not the first time nude pictures near sacred sites have drawn condemnation from local communities.

In June 2015, a group of Western tourists climbing Mount Kinabalu in Malaysia caused massive outrage and a subsequent deadly earthquake was blamed on their disrespect towards the sacred mountain.

It was only after court proceedings, a few days in prison and a financial penalty that the tourists were allowed to leave Malaysia.

In 2017 a Playboy model took part in a nude shoot on New Zealand's Mount Taranaki, angering Maoris who consider the mountain to be the burial ground of their ancestor.