DAKAR (Reuters) - Congolese authorities on Wednesday recaptured one of two escaped prisoners who were on trial for the killing of two U.N. investigators, while the second suspect narrowly eluded arrest, a senior military prosecutor said.

Evariste Ilunga Lumu and Kanowa Tshiaba, who escaped from prison in the city of Kananga on Monday night, are on trial accused of participating in the killing of Michael Sharp, an American, and Zaida Catalan, a Swede, in March 2017.

Sharp and Catalan were investigating a conflict in the central Kasai region between state security forces and the Kamuina Nsapu militia, which prosecutors blame for their deaths.

Tshiaba was arrested in the Nganza neighborhood of Kanaga, a bastion of support for the militia, which waged an insurgency in 2016-17, but Ilunga managed to slip away, said Timothee Mukuntu, Democratic Republic of Congo’s top military prosecutor.

“At the moment of the arrest, he (Tshiaba) was with Evariste Ilunga,” Mukuntu told Reuters. “The population of Nganza resisted so they (police) were able to extract Tshiaba but not Ilunga.”

Ilunga is the only defendant among more than a dozen on trial to have admitted having participated in the killings. An army colonel and an informant for the national intelligence service, the ANR, have also been arrested in connection with the case.

They deny involvement and have not been formally charged over the killings.

Ilunga and Tshiaba’s lawyer said on Tuesday that a third defendant in the case had also escaped, but Mukuntu said he had never left the prison.