Image caption Aaron Hernandez was arrested at his home on Wednesday morning

An American football star has been charged with murder after a fellow player was found dead last week in a Massachusetts industrial park.

Aaron Hernandez, 23, was taken in handcuffs from his home south of Boston in connection with the death of Odin Lloyd, 27, a semi-professional player.

Mr Hernandez was dropped from his team, the New England Patriots, after Wednesday morning's arrest.

The National Football League called the arrest "deeply troubling".

The league has struggled to improve its image after a string of cases involving dog fighting, gambling and homicide, among other criminal charges.

Mr Hernandez was also charged with several firearms violations. He pleaded not guilty to all charges.

'Just so you know'

Prosecutors say Lloyd was shot multiple times and that the former Patriots tight end had a dispute with him a few days before.

The dead man's family say he and Mr Hernandez were friends, and that Lloyd's girlfriend and Mr Hernandez's fiancee are sisters.

Prosecutor Bill McCauley said surveillance footage from Mr Hernandez's home showed him leaving earlier on the night of the killing with a gun.

According to authorities, Mr Hernandez and two friends picked up Lloyd at home at 02:30 local time (06:30 GMT) on 17 June. Mr Hernandez told Lloyd he was upset about an event at a nightclub days before.

Lloyd texted his sister about an hour later, according to prosecutors.

"Did you see who I am with,'' he wrote. He sister asked whom, and he later replied "NFL" and "Just so you know".

Minutes later, workers at the industrial park reported hearing gunshots, Mr McCauley said.

Civil suit

Image caption Aaron Hernandez, left, joined the Patriots in 2010 after playing for the University of Florida

Mr Hernandez's lawyer called the case "circumstantial" and "not a strong case", but a judge ordered him held without bail.

In a separate case, Mr Hernandez has been sued by a man who says the football player shot him in the face in February.

Alexander Bradley lost an eye in the shooting, but Florida police said they had dropped an investigation after Mr Bradley refused to co-operate.

Earlier on Wednesday, the Patriots said they would drop Mr Hernandez from the roster during the Massachusetts investigation.

"At this time, we believe this transaction is simply the right thing to do," the team said in a statement.

Mr Hernandez of Bristol, Connecticut, was drafted by the Patriots in 2010 after playing at the University of Florida. He played in the February 2012 Super Bowl, the NFL championship game. His contract was renewed last year in a five-year, $40m (£26m) deal.

He also signed an endorsement deal with footwear and apparel firm Puma in April.

A Puma spokeswoman declined to comment on Wednesday.