Mr Brown was taken into custody on Tuesday while returning to the US from Mexico, Maywood Police said in a statement on Wednesday.
“The San Diego Police Department Threat Management Unit along with other Local and Federal agencies took Mr Brown into custody after a warrant was issued for First-Degree Murder, for the death of his mother Myrtle Brown,” police said.
The former New England Patriot is waiting to be extradited to Maywood, Illinois, where his mother’s body was found on 16 September by family in a creek just 100 yards from her home. Both Myrtle Brown, 73, and Mr Brown were reported missing on that same day.
Her death was ruled a homicide as a result of assault injuries.
Although the former football player’s whereabouts have been elusive since he was last seen by family members, there has been some speculation that Mr Brown has been in Mexico as of late. TMZ reported last week that Mr Brown was allegedly dancing in red Nike swim trunks at a Tulum club.
On top of this, an Instagram account — which appeared to be linked to the former football player — showed strange videos of Mr Brown, including one video that police previously thought had been filmed in Playa del Carmen, Mexico.
In other videos, Mr Brown could be seen calling his mother’s death “fake news” and seemed to be mocking reports that he was “missing” by quoting “Finding Nemo.” He also made comments earlier this week on X referring to Mexican cartels.
This account as well as his official Instagram account seemed to have been taken down last week.
A funeral for Myrtle Brown was held on 29 September.
The 73-year-old’s sister, Sheila Simmons, said at the time of Mrytle Brown’s disappearance: “We’re going to find out what happened because it’s not normal for my sister to not answer her phone, not to respond to text messages.” She added, “People have been reaching out to her since Friday. No one was able to reach her. Now, I got the call this morning saying that she’s missing, so immediately I came out here and find out my sister is dead.”
A neighbour of Myrtle Brown, Carlos Cortez, also said last month that he had given authorities Ring doorbell footage, in which Mr Brown is allegedly seen burning his mother’s clothes. “They seen him taking out the trash, and they seen him have a bonfire where he burned all her clothes,” Mr Cortez said.