Five former Kansas City Chiefs players sued the team Tuesday for head injuries they sustained while playing.

Alexander Cooper, Leonard Griffin, Christopher Martin, Joseph Phillips and Kevin Porter are suing the team but not the National Football League, reports USA Today. They were members of the Chiefs in the late 1980s and early 1990s and played defense for the team.

The NFL agreed to a multimillion-dollar settlement that was announced in August for more 4,500 ex-players who sued the organization over their head injuries, reports ESPN. But the five players now suing the Chiefs were not part of that lawsuit. So they are now suing the team for unspecified financial damages.

According to the suit, the players are experiencing "post-concussion syndrome and latent brain disease" and they have displayed symptoms of chronic traumatic encephalopathy. But CTE – a form of brain disease – can only be confirmed after death through an autopsy of the brain.

The suit also asserts that the Chiefs ignored several decades of research showing that concussions cause lasting brain damage, referring to the injuries instead as "getting your bell rung'' or a "ding.'' And it accuses the team of telling players that the concussions were not serious.

"Defendant has known or should have known for many years that post-concussion syndrome and cognitive impairment occurs in football players," the suit says.