ANKARA 

New York Mayor Eric Adams on Tuesday called for nationwide gun control after four people were killed and one injured in a Manhattan office shooting.

"The response to shooters of this magnitude, mass shooters, cannot be vigils. It must be legislation," said Adams, speaking to ABC News.

Sharing new details of Monday’s attack, Adams said on ABC News that the headquarters of the US National Football League, housed in the building at 345 Park Avenue, seemed to be the goal of the shooter, who had traveled cross-country from Nevada in the US Southwest.

On a possible specific motive for the shooter – who killed himself after the incident – Adams cited a brain disease: "We're looking at his note that talked about CTE (chronic traumatic encephalopathy) ... but it is far from conclusive.” Some press reports said the shooter blamed the league for giving him the degenerative disease.

"When you look at the tapes ... there was just a total disregard for human lives," Adams added, saying that the gunman's meticulous approach was captured on security footage.

Immigrant police officer among victims

The mayor also said that President Donald Trump called him to express his condolences and praised the response of New York police officers.

Trump also extended condolences Tuesday to families of four people killed in the shooting, calling the gunman a "crazed lunatic."

"My heart is with the families of the four people who were killed, including the NYPD Officer, who made the ultimate sacrifice," Trump wrote on social media following the attack.

Trump, along with most Republicans, remains opposed to gun control.

Among the four dead was NYPD Officer Didarul Islam, 36, an immigrant from Bangladesh who was married with two boys, with a third on the way.

Adams ordered all flags on city buildings lowered to half-staff "as a mark of respect for the memory" of Islam.

A fifth victim remains in critical condition, fighting for his life.

Police Commissioner Jessica Tisch identified the lone shooter as Shane Devon Tamura, 27, from Las Vegas. Surveillance footage showed Tamura carrying an M4 rifle before dying from a self-inflicted chest wound.

Tamura had documented mental health issues, though his motives remain under investigation, Tisch said.