Malaysia's marine police on Monday captured a group of seven pirates from Indonesia who had been attacking vessels in the Straits of Malacca, the Star newspaper reported.
The seven were arrested after they threw three grenades at the police boat and the police damaged the engine on the pirates' vessel, marine police official Mohamad Kamsani Abdul Rahman was quoted as saying by the Star.
One of the captured pirates was wounded by the police gunfire and three escaped, the police official said.
"With the engine damaged, we managed to corner and detain the suspects after a 30 minute chase," Mohamad Kamsani said.
Police said that they suspected the gang had been behind thefts from ships worth 400,000 ringgit ($111,000) over the past year.
Unlike attacks in the Gulf of Aden, pirates around Indonesia and Malaysia tend not to seize ships and cargo, preferring to steal money and the personal property of crews.
Following a spate of pirate attacks in the South China Sea, the International Maritime Bureau in December warned ships to be vigilant.
Piracy in the Straits of Malacca, which were used by 70,000 ships in 2007, has been on the wane since 2005 when the Joint War Committee of the Lloyds Market Association added it to its list of war risk zones, sharply raising insurance premiums.