CLAYTON, Mo. — The man accused of shooting two police officers during a protest in Ferguson is slated to appear in court.

Jeffrey L. Williams, 20, is scheduled to be arraigned Wednesday on charges of felony assault, armed criminal action and a weapons offense.

Williams is accused of wounding a St. Louis County officer and a Webster Groves officer on March 12 during an early morning rally sparked by the resignation of Ferguson's police chief, Tom Jackson. Both officers survived.

Prosecutors say Williams told investigators he fired a gun but was aiming at someone else. Williams' attorney has countered that Williams was beaten by police into wrongly confessing, an assertion that St. Louis County Police spokesman Brian Schellman has called "completely false."

Williams was indicted by a grand jury in May and is jailed on $300,000 cash bond.

Ferguson has been the site of frequent unrest since Aug. 9, when white Ferguson officer Darren Wilson fatally shot 18-year-old Michael Brown, who was black and unarmed. The shooting led to a national "Black Lives Matter" movement.

Protests escalated again in March after the release of two U.S. Department of Justice reports, one of which cleared Wilson of criminal wrongdoing, echoing a decision in November by a St. Louis County grand jury. The other found significant problems in the Ferguson police department, including racial profiling and a profit-driven municipal court system.

Jackson, Ferguson's city manager and the municipal court judge all resigned within days of the report.

Both officers were monitoring a protest on the verge of breaking up outside the police station when shots rang out suddenly.

The Webster Groves officer was shot in the face; authorities have said he is expected to make a full recovery, but he has not yet returned to work. The St. Louis County officer was shot in the shoulder and is back on duty, though he isn't expected to resume full duties until August.

Audio of jail telephone calls from the St. Louis County Justice Center obtained by The Associated Press included one call in which Williams said he was having trouble with a group of people, prompting an exchange of gunfire. It wasn't clear to whom he was speaking.

"Nobody aiming at no police," Williams says. "I ran up the hill and he (an unidentified person) shot at the car. ... I shot back," Williams said.

In another conversation, Williams expressed concern about a possible lengthy prison sentence.

"Even though I was in the wrong, though, I should have just went the other way," he said. "Oh man, now I'm looking at 10 years."

Williams' attorney, Jerryl Christmas, has countered that his client has told him he never shot a weapon that day.