The attack occurred about a week after gunmen killed another police officer in Oyo State.
Gunmen attacked a police patrol team in Oyo State and killed a police inspector.
The police in the state confirmed the attack and said some of the gunmen also sustained gunshot wounds.
The attack occurred on Saturday at about 1:30 p.m. when the gunmen attacked a police patrol team at Budo Masalasi Border Post in Oyo State.
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The Oyo police spokesman, Ayanlade Olayinka, confirmed the attack on Sunday in a statement made available to journalists in Ibadan, the state capital.
About 10 to 15 gunmen attacked the patrol team led by an assistant superintendent of police, Entonu Shaibu, leading to the death of a police inspector, Aliu Oluwole.
The attackers also seized Mr Oluwole's AK-47 rifle with 30 rounds of ammunition, bearing breach number 4516.
"Yes, there was an attack on police operatives during which an Inspector, while courageously repelling the attack, paid the supreme price in the line of duty," the News Agency of Nigeria quotes Mr Olayinka as saying.
He said that the Commissioner of Police in the state, Femi Haruna, had ordered an immediate manhunt and comprehensive investigation into the attack.
According to him, preliminary findings indicate that some of the attackers sustained bullet injuries, and operatives are currently on their trail.
Mr Olayinka reassured members of the public that the command had put in place adequate security measures to safeguard lives and property in the state.
He urged residents to remain calm, vigilant and report any individuals with gunshot injuries.
He also called on residents to report anyone seeking medical attention for gunshots under suspicious circumstances to the nearest police station or security agency.
Mr Olayinka said that the police remained resolute in apprehending the perpetrators of the heinous act and bringing them to justice.
Recurring Oyo attacks
The attack on the police patrol team occurred about a week after gunmen attacked Aqua Triton Company in the state, killing a police officer and abducting a Chinese expatriate during the operation.
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Police authorities said the assailants stormed the facility on Friday, 16 January, in a commando-style operation and engaged security operatives attached to the company.
PREMIUM TIMES reported that in the attack, one police officer was shot dead while attempting to repel the attack.
Like in the case of the attack on the patrol team, none of the gunmen was apprehended, although the police said some of them were injured in the exchange of gunfire.
The attack on the patrol team also occurred about two weeks after gunmen suspected to be bandits attacked the National Forest Rangers' Office in Oloka village, Ikoyi-Ile area of Oyo State. Five rangers were killed in that attack, which occurred on 6 January. None of the attackers was apprehended.
