A crude bomb exploded in India's troubled northeast, wounding at least six passersby, and authorities searched for four Muslim traders believed to be abducted by a rebel group in the region.
The improvised device went off near the Manipur University complex in Imphal, the capital of Manipur state.
A police officer said that five of the wounded were being treated in a hospital. Two of them were in critical condition. The officer spoke on condition of anonymity as he was not authorized to talk to reporters.
No one has claimed responsibility for the attack. More than a dozen separatist groups are active in Manipur state and often stage hit-and-run attacks.
The rebels claim the local population is ignored by the federal government in New Delhi. Most locals are ethnically closer to groups in Myanmar and China than to the rest of India.
Meanwhile, authorities imposed an indefinite curfew in parts of Baksa district in neighboring Assam state after four Muslim traders were believed abducted by a faction of rebel group, the National Democratic Front of Bodoland, said state police Director-General Khagen Sharma.
Soldiers patrolled the area Saturday as tensions mounted following the recovery of some of the belongings, including bags and footwear, of those abducted, Sharma said.
In May, 45 people were killed in Baksa district, where police said gunmen from the Bodo tribe, which has long accused Muslims of entering India illegally from neighboring Bangladesh, went on a rampage, setting Muslim homes ablaze and firing indiscriminately at civilians.
The National Democratic Front of Bodoland, fighting for a separate homeland for the ethnic Bodo people for decades, has split into three groups.
Two of them are holding talks with the government for a peaceful settlement of their demand. However, one faction is still fighting in the region.