COLOMBO (AFP) - Sri Lanka has recorded a sharp rise in drug busts, suggesting the island is becoming a transhipment hub for heroin in Asia, a government minister said on Tuesday.

Information Minister Keheliya Rambukwella said record hauls of illegal drugs seized by police and customs pointed to a new smuggling operation using Colombo as a transhipment location.

"The quantities of illegal narcotics clearly suggests that this is not for consumption in the country, but to be re-shipped to some other countries," Mr Rambukwella told reporters.

He said Australia could be a possible destination.

About 10kg of heroin was found last week at the coastal resort of Hikkaduwa, a region where illegal boats going to Australia had been detected in recent years, the minister said.

Mr Rambukwella said the government was "deeply worried" about the incidents of narcotics smuggling and vowed the authorities would ensure maximum punishment for offenders.

In August, Sri Lanka customs found 260kg of pure heroin in a container at the Colombo port. The cargo had been sent from Pakistan and declared as grease.

Police are investigating a senior official from the Prime Minister's office who asked local authorities to waive demurrage charges and speed up the clearing of the container later found to hold one of the biggest hauls of heroin identified in Sri Lanka.

Mr Rambukwella said an independent investigation was underway into that smuggling attempt as well as several others.

Police said they had detected about 300kg of hard drugs this year compared to 15kg last year. Police said they suspected drugs were coming in from the Indian subcontinent.