Nigerian security forces searched Monday for a Swiss man and his Nigerian colleague after the pair were abducted by gunmen in the country’s southwest.

       The Swiss national was kidnapped along with a Nigerian citizen on Saturday, Ogun state police spokesman Abimbola Oyeyemi said. Two of the gunmen were shot dead by police while the others escaped with the hostages.

       The Swiss foreign ministry said Sunday night it is aware of a kidnapping based on media reports. A foreign ministry spokesman said the Swiss embassy in Nigeria is in touch with Nigerian authorities to learn more about the kidnapping.

       Nigeria has seen an increase in abductions for ransom by gunmen, with nearly 1,000 people kidnapped in the last six months. Most of them are children taken in mass abductions from schools.

       Many foreigners have been abducted in Nigeria over the years, mostly for ransom in the country’s volatile, oil-rich Niger Delta region.

       Last October, U.S. Special Forces successfully rescued an American held hostage in northern Nigeria after killing some of the gunmen holding him.

       Our Morning Update and Evening Update newsletters are written by Globe editors, giving you a concise summary of the day’s most important headlines. Sign up today.