An anti-littering volunteer and five students who went to Tanah Merah to do research and clean up a stretch of the beach have landed in hot water with the authorities.
They were stopped and questioned by the police for trespassing on state land, and are now waiting to hear if they will be prosecuted.
International Coastal Cleanup Singapore (ICCS) volunteer Marcus Tay, 31, told The Sunday Times he was there last month conducting a usual site recce when the police stopped him for trespassing.
The group of five students from the National University of Singapore (NUS) and several fishermen, who were also on the same stretch of beach, were questioned as well.
Mr Tay said he had seen anti-trespassing signs in the area but did not think they applied to where the group was.
"We've been cleaning up this area since 2010, and every time we go, we inform the National Environment Agency (NEA) so they can dispose of the rubbish we collect," he said.
The police confirmed that they have investigated Mr Tay and five students for wilful trespassing at the site on Oct 6. A spokesman said the matter had been referred to the Attorney-General's Chambers.
She said uninhabited coastal lands such as that Tanah Merah stretch had been used by smuggling syndicates to bring in contraband and illegal immigrants.
"These criminal elements often masquerade as members of the public, such as fishermen, to evade detection," she added. More importantly, she said, terrorist groups may exploit any vulnerability and deploy similar modus operandi to infiltrate the country.
In a joint statement with the Singapore Land Authority (SLA) and the NEA, the police said fences and signs have gone up at prominent points along the coast to indicate areas that are out of bounds to the public, and more such signs went up in September this year.
But Mr Tay and NUS biology lecturer N. Sivasothi, who supervises the five students, said they had not been told before that the area was out of bounds.
Mr Sivasothi, who is also co-ordinator for the ICCS group, said he intends to seek clarification from the SLA about access to other state land that the volunteers clean, including at Lim Chu Kang, Pasir Ris and Selimang beaches, and the Sungei Pandan, Kranji East and Lim Chu Kang mangroves.
"The volunteers just want to help, and their enthusiasm needs opportunities and space," he said. "And if we don't do it, marine trash accumulates on our shores and hurts marine life."
The police said members of the public should approach the relevant authority for permission to enter restricted land, and such requests will be assessed on a case by case basis.
Under the law, any person who wilfully trespasses on state land without a satisfactory excuse can be fined up to $1,000.
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