The country's Ministry of Foreign Affairs has issued an urgent warning to Nigerians not to be lured into illegal recruitment to join the military in another country's war.

The ministry issued the warning after Ukrainian authorities said they had found the bodies of two Nigerians who they said were killed in the war last year.

While Nigeria has not confirmed the deaths, Foreign Ministry spokesman Kimibi Imomotimi Ebinfa said in a statement on Sunday that "many Nigerians who have fallen victim to such tragic circumstances have been recruited into combat zones after being tricked into signing military service contracts."

Kenya has issued a similar warning to its citizens.

According to Nigerian authorities, investigative and security reports indicate that some citizens have been lured to war zones with promises of well-paying jobs, security jobs, educational opportunities, or immigration incentives.

In some cases, victims were forced to sign contracts in foreign languages without proper legal advice, and their travel documents were reportedly taken away upon arrival in the destination country.

Middlemen are also said to facilitate travel using tourist or other non-military visas.

Abinfa warned Nigerians not to accept such offers, stressing that they could not only endanger lives but also violate Nigerian and international laws governing the activities of mercenaries and the recruitment of foreigners.

Ukraine's intelligence agency estimates that more than 1,400 individuals from 36 African countries have been recruited to fight for Russia.

Ukraine itself has previously faced criticism for its efforts to recruit foreigners, including Africans.