7/11 -- 11:30 AM PT -- Christina Fulton released a statement saying, "On April 28th, 2024, around 5:30 pm I received urgent messages from friends of my son, Weston Cage regarding his deteriorating mental state, urging me to come help. When I arrived to offer support and console him, he was already in the midst of a manic rage. Within minutes, I was brutally assaulted and sustained serious injuries."

She continued, "Despite my desperate pleas to the responding Police officers to detain him for a mental health evaluation, the Police officers refused my request and neglected my urgent need for my medical attention. As a mother, I am deeply saddened and concerned about Weston’s on-going mental health crisis. It is imperative that he receives the help he desperately needs."

Weston Cage kicked off his day in police custody ... arrested for allegedly assaulting his mother Christina Fulton.

Nicolas Cage's son was arrested at 7 AM Wednesday for assault with a deadly weapon, and our law enforcement sources tell us Weston actually turned himself in -- with his lawyer by his side -- at an LAPD station.

We're told prosecutors charged Weston recently with assault with a deadly weapon and a warrant had been issued for his arrest.

Cage had to post $150k bond before he was released from custody later on Wednesday.

Our sources say the arrest is related to the incident with his mother we reported back in May -- Christina was seen out in L.A. with horrific bruises covering her face, following an alleged altercation with Weston.

We told you at the time that cops were investigating the incident as a possible felony battery. Weston had fled the scene by the time cops responded, and we're told Christina wasn't exactly forthcoming with details about the incident.

The way our sources put it ... she came to her son's aid during an emotional moment, and denied they'd had an argument.

We've reached out to Weston, so far no word back.