No group has claimed responsibility for the violence, but Nigeria faces a myriad of security challenges, including an insurgency in the northeast, kidnappings in central and northwestern states and separatist tensions in the south.
Gunmen stormed a mosque in southern Nigeria's Delta state, wounding 11 worshippers after attempting to kidnap the imam, police have said.
No group has claimed responsibility for the violence, but Nigeria is facing a myriad of security challenges, including an insurgency in the northeast, kidnappings in central and northwestern states and separatist tensions in the south.
The early morning assault on Friday occurred at the mosque in Ughelli, near the oil city of Warri.
"Eleven (people) were injured," police spokesman Bright Edafe said.
He said an investigation was underway to find the suspects.
Local media quoting a community leader and a victim reported that an imam was kidnapped during the attack.
Police rejected the claim, saying, "it was the intention to take him (the imam) but they (the gunmen) did not succeed."
Kidnappings are common in Nigeria and are largely committed for financial gain by rag-tag groups of bandits which have no known ideological motivation.
Security in Delta state had improved compared to the early 2000s when militant groups frequently attacked oil facilities or kidnapped oil workers.
But in neighbouring southeastern states, scores of recent assaults have been blamed on the outlawed separatists, the Indigenous People of Biafra (IPOB) group and its armed wing, the Eastern Security Network.
IPOB, which seeks a separate state for the ethnic Igbo people, has repeatedly denied responsibility for the violence.
President Muhammadu Buhari, who came to power in 2015 and was re-elected in 2019, is under pressure to take action on Nigeria's security problems before he steps down after elections due next February.