A foreign ministry statement late Tuesday accuses Nicholas Haysom of diplomatic overreach that violated the Horn of Africa nation's sovereignty, declaring him "persona non grata." He arrived as envoy a few months ago.
Haysom had questioned the legal basis used in the arrest last month of Mukhtar Robow, a former al-Shabab spokesman who defected from the group in 2017, and whether U.N.-funded regional police in the Southwest were involved.
Ethiopian troops who are part of the African Union force in Somalia and Somali police arrested Robow days before the regional election in which Robow had been a leading candidate. Deadly protests followed. Ethiopia has not commented.
Robow was flown to Somalia's capital, Mogadishu, and has been held in a prison run by Somalia's intelligence agency. U.N. deputy spokesman Farhan Haq said the U.N. was looking into the matter before determining what steps to take.
Haysom, who was outside Somalia, did not respond to a request for comment. Instead, he and the spokesman for the U.N. secretary-general late Tuesday issued statements strongly condemning a mortar attack that hit the main U.N. compound in Mogadishu earlier in the day. Seven mortars landed inside the compound, leaving two U.N. staffers and a contractor with non-life-threatening injuries, Haysom's statement said. Al-Shabab claimed responsibility.
Robow's arrest has been seen as a high-profile test of Somalia's treatment of defectors from the al-Qaida-linked al-Shabab, Africa's most active extremist group. Somalia's government welcomed his defection but not his popular candidacy to lead Southwest state, which took some officials by surprise.
In confirming Robow's arrest, Somalia's security ministry cited the federal government's ban on his candidacy, which said he had not completed the defection process. The ministry also alleged that Robow had failed to renounce extremist ideology, and accused him of mobilizing armed forces.
A joint statement by the United States, more than a dozen countries, the AU mission and the United Nations expressed concern after the arrest and protests. Haysom's letter to Somali authorities, seen by The Associated Press, questioned the legal framework of Somalia's defection process and asked how Somali authorities were able to detain Robow beyond the normal 48 hours.
The letter also questions the circumstances around civilian deaths during the protests and urges that they be "thoroughly and promptly investigated."
Associated Press writer Jennifer Peltz at the United Nations contributed.
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