Warship makes second big drug bust

Australian warship HMAS Melbourne has made another multimillion dollar drug bust on the high seas off Tanzania, the second in a week.

A Melbourne boarding party seized 190 kilograms of heroin aboard a drug smuggling vessel on Friday.

That follows the seizure and destruction of 385 kilograms of heroin from a vessel in the same area on February 5.

Based on possible street values, the two big drug hauls were worth more than $1 billion.

Melbourne captain Commander Brian Schlegel said his crew was excited by the second large seizure in short succession.

"This is a good day for HMAS Melbourne but not too good for the drug smugglers," he said.

Melbourne is patrolling in the western Indian Ocean region under the command of the multinational Combined Task Force 150, which conducts counter-terrorist and counter-narcotics operations.

CTF-150 is currently commanded by Australian navy Commodore Daryl Bates, who said the combined maritime forces units had now seized 1.3 tonnes of heroin with an estimated $2.7 billion street value.

HMAS Melbourne has experienced a busy deployment.

In October, the ship disrupted a pirate gang off Somalia and then made three amphetamine busts, totalling 23.8 kilograms.

After testing, seized drugs are usually destroyed by dumping them overboard.