Two Molotov cocktails were thrown at the office of a news magazine which is embroiled in a dispute with Indonesian police over an article about alleged corruption, police said on Tuesday.
The homemade firebombs were thrown at Tempo magazine's Jakarta headquarters before dawn on Tuesday but did not ignite or cause damage, a police spokesman said.
"Two Molotov bombs without wicks were thrown this morning in front of Tempo's office. It happened at around 3:00 am. The bombs didn't explode and nobody was hurt," police spokesman Boy Rafli Amar said.
"We're trying to find the culprits. We suspect two people on a motorcycle threw them."
Police last week threatened to sue Tempo over an article alleging massive corruption among senior police generals accused of amassing millions of dollars in bank accounts from illegal activities.
The threat was not related to the corruption allegations, however, but to the magazine cover art which depicted a police officer with piggy banks. Pigs are considered haram (forbidden) in Islam.
Police were unavailable to comment on reports in the local media on Tuesday, saying they had dropped the threat of legal action.
President Susilo Bambang Yudhoyono has demanded a thorough investigation of the corruption allegations after revealing that he had been swamped with text messages from the public appealing for action.
"The issue on the bank accounts which belonged to a number of high ranking police officials has spread widely (among the public)," he said.
"Please take an action," he told the police.
"If anyone broke the law, they must be punished. Otherwise, explain that to the public."
Anti-corruption and human rights activists however questioned how the police, widely considered one of the most corrupt institutions in the country, could be trusted to investigate graft allegations against top officers.
Yudhoyono himself admits the force is part of a "court mafia" including prosecutors and crooked judges who run the mainly Muslim country's judicial system in favour of powerful interests.