Johannesburg There will be an increased police presence at Mossel Bay beaches where drums containing cocaine have washed ashore, police said on Friday.

"Police helicopters... will observe the area," said spokesman Captain Malcolm Pojie.

There would be regular patrols at ports of entry as well as police patrolling along the shoreline and in the water.

Four batches of cocaine, with an estimated street value of about R68 million, have been found in packets and in brick shapes contained within drums floating off Mossel Bay beaches since Christmas.

On Friday, Pojie said tests -- expected to determine exactly what substances were in the bricks and whether the cocaine had been "cut" or processed, or was still in its pure or raw form -- had not yet been completed.

The origin of the drums was not known but they could have been dropped off a ship, said Pojie.

"It is one of the possibilities."

The latest haul -- a blue drum containing a black bag with 25 cocaine bricks -- washed ashore between Hartenbos and Klein Brak River on Wednesday afternoon.

A similar drum of cocaine bricks was found on Tuesday off Rheebok Beach.

Last Saturday, a drum was found near Pinnacle Point and on Christmas Day 25 packets of cocaine were found floating in a drum at Hartenbos Beach.

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