Harare - Police have arrested a leader of Zimbabwe's war veterans after they accused President Robert Mugabe of "dictatorial" behaviour in an exceptional show of dissent, lawyers said on Thursday.Veterans of Zimbabwe's 1970s independence war, who have previously been loyal Mugabe supporters, issued a statement last week bitterly denouncing him.Douglas Mahiya, spokesperson for the War Veterans Association, was arrested late on Wednesday in Harare, according to Zimbabwe Lawyers for Human Rights (ZLHR)."Information presently at hand is that the police are charging him with subverting a constitutional government and insulting the office of the president," the lawyers said.A Mahiya family lawyer confirmed the arrest to AFP, but declined to comment further.The association's secretary-general, Victor Matemadanda, was also taken from his rural home in Gokwe after being summoned for police questioning, ZLHR said."His whereabouts are currently undetermined, as are the charges or allegations against him," it added.Police declined to comment on the two cases, a day after Mugabe vowed to punish the unnamed authors of the veterans' criticisms."When we find out who the people were, the party will discipline them. The punishment will be severe," Mugabe said on Wednesday.In a surprise change of stance, the liberation war fighters last week vowed not to support Mugabe, 92, if he sought re-election.