LUSAKA, Aug 27 (Reuters) - Zambian opposition leader Brian Mundubile and his running mate, Makebi Zulu, are in police custody after being questioned "in connection with an alleged offence of treason," the Zambia Police Service said on Thursday.
The arrest came amid heightened political tensions following Zambia's August 13 election, in which Mundubile came second to President Hakainde Hichilema. Mundubile has claimed the election was fraudulent, which Hichilema denies.
Police did not immediately provide details of the allegations underpinning the treason investigation. They said that "warn and caution" statements had been recorded, a step typically preceding formal charges.
Mundubile's lawyers were not immediately reachable for comment.
Treason is a serious offence in Zambia and carries severe penalties upon conviction.
Mundubile was summoned for questioning last week over alleged national security threats, following the arrests of several other high-profile opposition members which drew condemnation from international human rights groups.
Mundubile has said in previous statements that the allegations were fabricated.
(Reporting by Chris Mfula; Writing by Anathi Madubela;Editing by Nellie Peyton, Andrew Heavens and Cynthia Osterman)
