BANGKOK, Aug. 31 (UPI) -- A grenade exploded outside the main office of Thailand's National Broadcasting Service Tuesday, a government spokesman said.
Spokesman Panitan Warranayagorn told the Bangkok Post the blast damaged a van and four cars but caused no injuries.
Police said they believe it was launched from a nearby tollway.
A series of explosions have rocked the Thai capital in recent weeks.
Last Thursday a grenade injured a security guard at a shopping complex.
On July 30, a man in his 30s was injured when a grenade hidden in a plastic garbage bag detonated.
That attack happened less than a week after a small bomb exploded at a Bangkok bus stop, killing one person and injuring 10 others.
In March, an M79 grenade was fired into a military compound, injuring two soldiers.
