After overnight violence left three dead in Bangkok, an election commissioner said Thursday it is "highly unlikely" that Thailand will be able to hold July 20 elections because of political unrest that has disrupted necessary preparations and forced commission members to flee a meeting.

Caretaker Prime Minister Niwattumrong Boonsongpaisan was meeting with the Election Commission at an air force academy outside Bangkok to discuss whether the controversial polls could be held July 20 or would have to be delayed owing to the political conflict. He had chosen the location for security reasons to avoid protesters in the capital who are opposed to the election and are calling for an unelected, appointed prime minister.

About 100 protesters who had driven in motorcades from central Bangkok entered the compound through a side entrance, blowing whistles and waving Thai flags. Riot police stationed outside apparently allowed them to enter, followed by protest leader Suthep Thaugsuban.

Niwattumrong and several Cabinet ministers at the meeting were notified by security officers that protesters were approaching. The officials ended the meeting, got into their cars and were driven away.

After the upheaval, Election Commissioner Somchai Srisuthiyakorn said, "It looks like it will be impossible for the general election to take place on July 20."

According to a strict timetable, a royal decree must be issued by May 22 for the election to occur on July 20. But a number of issues need to be sorted out between the government and the Election Commission before the royal decree is issued, said Somchai, who is known to support the protesters.

"Looking at this time frame, it is highly unlikely that it will happen in time," he said.

If the July date doesn't work out, the vote could be delayed by a few weeks or longer, said the commission's secretary-general, Puchong Nutrawong.

Thailand's long-running political crisis deepened last week when the Constitutional Court removed Prime Minister Yingluck Shinawatra for nepotism, along with nine Cabinet members, in a case that many viewed as politically motivated.

The protesters are pushing the Senate and the nation's courts to intervene in the crisis to install a "neutral" prime minister, but the government says that is a threat to the nation's democratic system and would be tantamount to a judicial coup.

The predawn attacks near Bangkok's Democracy Monument, where some protesters are camping out, marked the latest spasm of violence to hit the capital since protesters launched a campaign to oust the government six months ago.

Police Col. Krailert Buakaew said at least three grenades were detonated and machine guns were fired at protesters in the small encampment. He said the dead included one sleeping protester and a volunteer guard. He said investigators are collecting evidence but have so far found only puddles of blood at the scene.

The Erawan Medical Center said that the toll was three dead and at least 21 wounded. The attack brings the nationwide toll since protests began in November to 28 dead and about 800 wounded.

The Associated Press