A Polish immigrant involved in Poland's Solidarity movement in the 1980s is on a hunger strike after being fired from a Loveland, Colo., Wal-Mart Distribution Center.

Ryszard Tomtas was fired Tuesday for "horseplay" he said, but he believes he was really fired because he was trying to organize a union at the center.

Tomtas, 46, chained himself to a stop sign in front of Wal-Mart on Thursday but police asked him to unchain himself to avoid an arrest. Police told him he can protest in front of the building as long as he doesn't block the right-of-way.

The married father of a young son said he will drink only water until he gets some "positive impact" from Wal-Mart. He said he can't get unemployment because he was fired.

Tomtas said that he has contacted the U.S. Equal Employment Opportunity Commission to a file wrongful termination complaint against the company.

He was suspended on Feb. 25 for horseplay with a co-worker and then called Tuesday to say that he had been fired.

Tomtas claims he was fired because he signed a union card and the union notified Wal-Mart he would try to organize a union at the center, a charge which Wal-Mart denied in a written statement.

"It appears that he is not willing to face the fact that he was not terminated for his support of the union, but rather for a violation of Wal-Mart’s company policy on workplace violence," the statement said.

A union organizer for the United Food and Commercial Workers Local 7 said that the union is investigating. An attorney for Local 7 said the union plans to file charges against Wal-Mart on Tomtas' behalf next week.

“There appears to be some link, at least from our perspective, between his firing and the union. We will file a charge based on that; Wal-Mart can plan on it," attorney Deangelo Starnes told the Loveland Daily Reporter-Herald.