Say he has 'surrendered' - as shootings surge across US over July 4th weekend and Donald Trump warns he's ready to intervene (21 Pics)

At least 41 people were injured and at least nine killed following a troubling spike of shootings in the Big Apple across the holiday weekend. A spokesperson for the NYPD said the majority of the incidents occurred within a 15-hour time period.

Shootings in New York City have doubled every week for the last three weeks. In the last seven days alone, the city has experienced a 142 percent surge in shootings compared to the same time period last year. Speaking during a radio interview Sunday morning, Kelly blamed the cause of the chaos on de Blasio's decision to slash $1 billion from the NYPD budget earlier in the week.

NYPD Commissioner Dermot Shea has previously disbanding an anti-crime plainclothes unit that had focused on stopping people and searching for guns.

'Here, the mayor eliminated the anti-crime units, which were probably the most effective tool that existed in the department for decades to fight violent street crime,' Kelly said. 'So that was a direct signal of surrender.'

Earlier, President Donald also criticized de Blasio, in addition to New York Gov. Andrew Cuomo, warning them that he's 'ready' to intervene if necessary.

'Shootings up significantly in NYC where people are demanding that [Gov. Andrew Cuomo] and [Mayor Bill de Blasio] act now,' Trump continued. 'Federal Government ready, willing and able to help, if asked.' Trump also reference the rise in violent gun crime in Chicago, which appeared to experience the worst of the violence this weekend as 77 people were injured in shootings and 14 were killed, including two children.

Memphis, Omaha, Cleveland and several other cities were also rocked by a spate of shootings amid the holiday revelry. In total, 37 have been killed in shootings across the US.