Two Bay State couples have filed a class action lawsuit charging that their three children - and perhaps thousands of others - have developed autism from mercury-containing childhood vaccines.

"Something's going on here," said Mike Chmura of Waltham, who believes the mercury in the vaccines may be the reason his 5-year- old son, [Evan Chmura], has autism.

`SOMETHING'S GOING ON HERE': Susan Chmura plays with her son, Evan, 5, whose autism, the Chmura's charge, may have been caused by mercury-containing vaccines. STAFF PHOTO BY TED FITZGERALD