US President Joe Biden has called on banning the sales of assault-style weapons to regular civilians, addressing Pennsylvania supporters on Tuesday regarding gun crime and prevention. 

"I'm determined to ban assault weapons in this country," he said. 

His trip to Pennsylvania is the first of three trips going to take place in the next days as he garners support for November's midterm elections. 

Furthermore, he denounced Republican attacks on the FBI after the agency raided former US President Donald Trump's Mar-A-Lago residency. 

Read next: Trump sues FBI over Mar-a-Lago raid

"It's sickening to see the new attacks on the FBI... There is no place in this country for endangering the lives of law enforcement. No place. None. Period. I'm opposed to defunding the police, I'm also opposed to defunding the FBI," Biden said in a speech in Pennsylvania. 

Biden's bid to curb gun violence

In late July, the US House of Representatives passed a bill that, if signed on, would ban assault weapons, marking a first in decades in light of a mass shooting epidemic in the country.

See more: US: Gun makers made over $1 billion in 10 years from rifle sales

The United States is deeply divided about reforming gun laws despite an erratic episode of gun violence that has seen an escalation in recent months. The bill passed the House floor with the support of two Republicans who joined efforts with their democratic counterparts and backed the measure.

The bill is "a crucial step in our ongoing fight against the deadly epidemic of gun violence in our nation," US House Speaker Nancy Pelosi said.

The recent spike in tragic shootings has pushed guns to the forefront of a national debate as US leaders grapple with how to reduce the alarming rate of violence.

Two shootings in May that left 21 people dead, mostly young children, at an elementary school in Texas and 10 Black grocery patrons dead in upstate New York revived the US' bitter debate over gun regulation.

Read more: US school shootings peak at record high of 193 last academic year

US President Joe Biden pleaded for lawmakers to pass stricter gun control laws, including a ban on assault weapons, in a bid to clamp down on unprecedented levels of mass shootings across the United States that have been turning American communities into "killing fields".

Profit from misery

Gunmakers in the United States have seen a tremendous hike in earnings from their sales of AR-15-style rifles, a US House Oversight Committee probe revealed on Wednesday as the country undergoes a mass shooting crisis and while lawmakers call for holding the industry accountable for crimes committed using their products.

"Gun manufacturers collected more than $1 billion from the sale of AR-15-style semiautomatic weapons in the last decade - and sales are increasing as gun deaths and mass shootings rise," a memorandum on the Oversight Committee investigation said. 

Firearm manufacturer Daniel Defense earned more than $120 million in revenue from selling AR-15-Style rifles in 2021, a three-fold increase from the amount it made two years earlier in 2019.

Gunmaker Ruger's earnings, on the other hand, witnessed a near-three-fold increase over the same time period, going from $39 million in 2019 to more than $103 million in 2021, the memorandum revealed.