Ukraine's new reform-minded government faces its first major test of its commitment to the rule of law _ as opposed to the law of the street _ with the country's police chief under investigation for allegedly assaulting the capital's mayor, reported The Associated Press. Kiev mayor Leonid Chernovetsky accuses Interior Minister Yuriy Lutsenko of punching him in the face after the two argued during a government agency meeting on Friday. «Such beastly behavior disgraces Ukraine,» Chernovetsky said in a statement later in the day. Lutsenko begs to differ. He says he slapped Chernovetsky's face but contends it was the mayor who initiated the fight by first publicly defaming him, then kicking him in the knee. «I slapped Chernovetsky on the face _ all the governors saw it,» Lutsenko said on a television talk show. «I am not going to apologize, because I believe it is an absolutely base thing to do _ to defame a person for something he didn't do. «And it is absolutely low to kick someone in the knee under the table because I know who does that _ convicts in prison do that.» The Kiev Prosecutor's Office said Friday that Chernovetsky suffered minor bodily harm and that a criminal case has been opened «in connection with the other participant in that event.» If convicted, Lutsenko could be sentenced either to up to one month of community work or up to one year of internal exile, AP reported.