At least 11 people were killed when unidentified miscreants sprayed fuel on a bus and set it afire in San Salvador in the capital of El Salvador, officials said.
The bus was burnt Sunday night in Mejicanos municipality in San Salvador.
"Unknown people ambushed the bus and sprayed it with fuel and set it on fire, which evidently was a terrorist act," Public Security Minister Manuel Melgar was quoted as saying on Monday by Xinhua.
Seven people were injured in the incident and taken to hospital, witnesses said.
Policemen broke the windows of the bus and rescued some passengers, and later four people were arrested in this connection, Carlos Ascencio, director of the Civil National Police said.
Criminal outfits in El Salvador have asked transport companies to pay them in exchange of not attacking their vehicles.