Suthep Thaugsuban, who served as deputy premier in the Abhisit government, was questioned by Thailand's Department of Special Investigation, MCOT online news reported.
Red Shirt protesters and their United Front for Democracy against Dictatorship party rallied in support of former Prime Minister Thaksin Shinawatra in April and May of 2010, demanding the reinstatement of Thaksin, who was overthrown by the military in 2006 over corruption allegations.
The demonstrations turned violent as the army eventually moved in to clear the streets.
Exploding whale video goes viral on Internet
Man behind Doritos Locos Tacos passed away on Thanksgiving