Gunmen killed a Nigerian traditional monarch and kidnapped his wife after raiding his palace, police said, as outrage grows over a spate of abductions across the country. Attackers stormed the palace of Oba Aremu Olusegun Cole in south-western Kwara state, shot him dead and abducted his wife and another person on Thursday. State police said they had launched an investigation and stepped up security. Similar attacks regularly take place in Nigeria, which is struggling with a security crisis on several fronts. Two traditional rulers were shot dead by unknown gunmen in neighbouring Ekiti state on Monday. Last year the president, Bola Ahmed Tinubu, came to power promising to address insecurity – including jihadists in the north-east, criminal militias in the north-west and growing intercommunal violence in the centre of the country – but critics say violence is spinning out of control. The Nigerian risk consultancy SBM Intelligence said it had recorded that 3,964 people were abducted since Tinubu took office in May. At the start of the year, criminals abducted five young sisters near the capital, Abuja, and killed one when a ransom deadline passed, prompting a national outcry.