A Singaporean who died while climbing Adam's Peak in Sri Lanka last month suffered a heart attack, Sri Lankan police told The Straits Times.

Tan Ah Hiang, 55, was part of a Buddhist tour group of about 20, which began the climb just after midnight on March 17.

The 2,243m-high Adam's Peak, also known as Sri Pada, is about a four-hour drive from Colombo. It is said to be a holy site, and is a popular destination for Buddhist pilgrims, especially in the run-up to Vesak Day.

Tan began having breathing difficulties at about 3.30am, after a 5km trek. He collapsed, and died on the way to hospital.

Anil Jeyasinghe, the officer in charge of Nallathaniya Police Station, which handled the case, said on Wednesday that a post-mortem showed Tan died of a heart attack caused by coronary blockage.

He told The Straits Times that about 30 people had died during climbs since 2013, mostly due to heart attacks. The route itself was safe, he stressed. "There has been no case of death by falling along the route."

In fact, much of the route from the base to the summit is laid with cement and stone steps, and the path is fringed with electric lights to allow for night-time visits.

Tan's group had wanted to reach the summit before 6am to see the spectacular sunrise.

In February and March, over 10,000 pilgrims can be expected during the festive "Poya" days, a Sri Lankan Buddhist holiday, said Jeyasinghe.

Tan, a storekeeper who was single, had been travelling with his elder brother and younger sister.

Elder brother Tan Ah Boon, 60, told The Straits Times that climbing Adam's Peak was "not particularly dangerous, provided you pace yourself and know when to stop when you cannot continue".

"We felt partly responsible for his death; we should have stopped him from climbing so quickly. But we have since moved on from the tragedy," he said.

"Life has to go on, and we intend to continue on such trips," he added, describing his brother as "a highly positive and kind person".
(With inputs from The Straits Times)