It could be but,to assume anything other than terrorists after 9-11 is potentially self destructive.
Algeria blast Jan 20 and this on Jan 20:
http://www.channelnewsasia.com/stories/afp_world/view/67163/1/.html JAKARTA : More than 50 people were injured as fire broke out at an Indonesian petrochemicals plant following two explosions, police said.
At least 52 people were taken to hospital with burns as the fire engulfed several chemical tanks at the Petro Widodo premises in Gresik, near the city of Surabaya in East Java province.
"There was the sound of two explosions before a column of black smoke rose into the sky," said Slamet, a duty officer in Gresik.
Gresik district chief detective, Sudibyo, told ElShinta radio some workers might have been trapped by the blaze. The plant employs some 450 people.
He said thick black smoke was irritating the eyes of local people. Firefighting efforts using water jets appeared to be ineffective and the fire was spreading further into the compound, he said.
Gresik district police chief, Sopandi, told the radio station that the blaze swept through several chemical storage tanks and was now threatening many others containing ammonia.
"Only masked firefighters can approach the blaze," Sopandi said. Flames were 50 meters (165 feet) high and smoke could be seen for miles around.
An office worker some two kilometers (a mile) away from the plant told ElShinta he was in a meeting when he heard an explosion and the ground trembled "just like an earthquake."
Fifteen fire engines were at the scene and reinforcements had been ordered from Surabaya.
There was no immediate information on the cause of the explosions. Petro Widodo is a subsidiary of state petrochemical company Petrokimia.
Gresik, a densely populated industrial center, hosts cement and chemical industries.
- AFP