US footballer Junior Seau killed himself, autopsy shows Seau's death came at a time of increased scrutiny of the effects of head injuries in football and the potential for such injuries to contribute to depression and long-term damage in professional players. Over 1,500 former football players have sued the NFL over head injuries. On Thursday, 100 other retired players filed a lawsuit against the league on the same grounds in federal court in Atlanta. The league disputes the claims in the suits, which accuse it of concealing links between football and brain injuries. "Any allegation that the NFL intentionally sought to mislead players has no merit," Greg Aiello, a spokesman for the league, said in a statement. "It stands in contrast to the league's actions to better protect players and advance the science and medical understanding of the management and treatment of concussions," Aiello said. The league, in the face of criticism, has focused in recent seasons on health and safety issues. It has cracked down on hits to the head, and stiffened rules that prohibit players using their helmets as a weapon through headfirst contact, which is subject to fines and suspension for repeat offenders. Seau's death was at least the third suicide by a former NFL player since February 2011, when former Chicago Bears defensive back Dave Duerson killed himself and left a note asking that his brain be studied. Less than a month ago, former Atlanta Falcons safety Ray Easterling shot himself to death at age 62. Easterling, a plaintiff in one of the suits against the NFL, had been diagnosed with dementia, and his wife said after his death that she wanted the league to "take responsibility." Seau, who played for the Miami Dolphins and New England Patriots after leaving the Chargers, retired after the 2009 season.