Johnny Manziel: Dallas Cops Open Investigation

Johnny Manziel is now the subject of a Dallas PD investigation.

24 hours after cops said they would not arrest Manziel for allegedly beating Colleen Crowley last weekend -- police now say they will investigate because Crowley is cooperating.

Dallas PD says Crowley filed a complaint on Friday. Police have not revealed details of the report, but say they will thoroughly investigate to see if criminal charges should be filed.

Fort Worth police initially took a report from Manziel's now ex-girlfriend at her home after the alleged incident, but noted she did not want any photos taken and was uncooperative with responding officers.