Lionel Messi's brother Matias has been arrested for the illegal possession of a firearm after a gun was found on his blood-splattered speedboat, it's been reported

The eldest brother of football superstar Lionel Messi has been arrested for the illegal possession of a firearm after a gun was found on his blood-splattered speedboat, it's been reported.

Matias Messi, 35, was detained in a hospital in Rosario, northern Argentina, where is recovering from a fractured jaw and other injuries sustained from what he claimed was a boating accident.

Matias said he fractured his jaw and nose after hitting a sandbank while driving a speedboat on the Panama River.

But police investigating the incident found an unregistered 380-calibre pistol on the boat he was piloting, which had 'numerous blood stains', according to the prosecutor who ordered his arrest.

Argentinian news outlets published pictures of the blood-covered motor boat, which was left at a fishing club in the town of Fighiera, close to Matias' home on a private estate in General Lagos.

Local reports said he could face a prison sentence of up to six months if convicted.

This isn't the first time Matias, who is five years older than his famous brother, has had brushes with the law for allegedly illegally carrying a firearm.

The Barcelona star's brother, who has been linked with known criminals in the past, was held for 16 hours in a prison cell for in 2015 after officers found an an unlicensed.22-caliber gun in his car.

He was also arrested in 2008 for allegedly having a loaded gun in his belt.

Matias' lawyer, Ignacio Carbone, said yesterday the Messi family disputes the police account that a gun was found on his boat.

He said: 'I have been able to talk with the relatives who have ruled out that he has a weapon.

'The family have denied the existence of any gun, and say that this information is totally false.'

Blood found all over Matias's motor boat (pictured). A handgun was also found in the vessel

But the prosecutor of the case, Jose Luis Caterina, said in a press conference that the gun was found by officers from the Criminal Investigation Bureau and the discovery of the weapon was 'transparent, clear and legitimate', and that it 'was not planted.'

He added that 'three different security forces' had worked on the case and that the gun was 'ready to be fired' containing six bullets.

The investigation began on Thursday after a villager found Matias injured and adrift on a boat on the Panama River 20 miles south of Rosario, northern Argentina.

He claimed he had been navigating the boat alone when it had crashed after hitting a sandbank.

The villager reportedly wrapped him in a sleeping bag and piloted the boat to a nearby fishing club where Matias was rescued and taken to Rosario's Parque sanitarium hospital.

Matias reportedly told a security guard he had cut his face after colliding with a sandbank

According to the hospital's director Carlos Lovesio, he underwent surgery for a fractured jaw and nose, and other facial injuries.

Following the discovery of a gun on his boat, lawyer Ignacio Carbone tried to delay the issuing of an arrest warrant claiming his client 'cannot express himself very well and has trouble speaking', according to reports.

Prosecutor Jose Luis Caterina said that, although police were still investigating the circumstances of the incident, he would be arrested initially for the illegal possession of a firearm.

Matias had reportedly met with his probation officer two months ago in relation to the last time he was arrested and charged with carrying an unregistered gun.

The boat was left at a fishing club in the town of Fighiera a 20-minute drive from Matias's home on a private estate in General Lagos

In October 2015, he had a violent spat with police officers following the discovery of an unlicensed gun in his car.

Matias reportedly wrestled with officers after refusing to show them documents for his Audi A5 or let them search the vehicle during a routine stop.

Two officers were reportedly taken to hospital with foot and knee injuries after the incident and Matias was held in a police station cell for 16 hours.

He later blamed his famous brother for the altercation, telling journalist Leonardo Faccio: 'I was mad, you get a little mad because you see him everywhere, Even today I'm not used to it.'

Matias was instructed to teach football as part of a probation order and ordered to pay a fine of £415.

Matias is the eldest brother of Barcelona superstar Lionel Messi (pictured celebrating a goal against rivals Real Madrid in April)

He was also ordered to stay off drugs and drink and pay a fine of around €470 (£415).

He was also arrested in 2008 for allegedly having a loaded gun in his belt.

In 2016 a photo emerged of him in a group of alleged criminals, including several men wanted by Interpol for murder and drug trafficking.

And in April 2011, Matias survived an assassination attempt after his house was sprayed with bullets in a drive by shooting.

Messi's other brother, Rodrigo, meanwhile, was charged with brandishing a gun in Spain after an altercation with cyclist he accused of driving too close past him.

He reportedly waited for the cyclist at a petrol station and threatened him with the firearm.