Explosion reported in Al-Mayadeen, in the Deir az Zor countryside, also wounds several people.
The election has been dominated by issues such as housing and immigration, and follows a decade of fragile governments.
Governing party's pro-EU candidate and a right-wing nationalist are set for a decisive second-round showdown on June 1.
For years, these tattoos symbolised defiance against the Indian government. Now, thousands are erasing them.