MIAMI (NewsNation Now) — Across the country, it was a violent weekend.

In Chicago, fifteen people were shot and two killed at a party Sunday. An off-duty officer was shot when gunmen ambushed his car while he was stopped at a traffic light.

In Miami Beach, officers arrested more than 100 people over the weekend using pepper spray to disperse an unruly crowd of spring breakers. They confiscated guns and drugs from the revelers.

In Indianapolis, 12 people were shot over the weekend and seven were killed, including a 7-year-old girl.

In New York, five people were shot in Brooklyn at an illegal party.

In Los Angeles, an infant was shot, capping off what has been the most violent time in the city in two decades.

“We are seeing military-style weapons with high-capacity ammo rounds. At one homicide scene alone we collected almost sventy ammo rounds,” said Los Angeles Police Department Deputy Chief Regina Scott.

Homicides have been on the rise nationwide. In 2019, there were 6,087 murders in the US. That rose 33% to 8,077 murders in 2020.

From 2019 to 2020, New York City saw a 41% increase in murders. Chicago saw a 55% increase and Los Angeles saw a 34% increase.

Former FBI Agent and law enforcement expert Phil Andrew says stress from the pandemic is a major factor in the spike in violence.

“Well, I think a lot of these are problems that existed before the pandemic and before the racial unrest. What we are seeing is any problem we were not dealing with effectively before those big, big challenges were really exasperated,” said Andrew.

Domestic violence has been on the rise, as has unrest and racial tension.

“The unrest has unraveled police. They are working overtime — working just to keep streets safe and respond to protests,” says Andrew.

Andrew says many cities, like LA and New York City, were making good progress in 2019 driving down gun violence. He worries the spike now won’t be easily revered even once the pandemic is over.

“There is an incredible amount of strain on the 18,000 law enforcement organizations in the country. We are starting to see that because we see the uptick in officers being shot at. We have seen an uptick in officer suicides. And now we are seeing increased early retirement,” says Andrew. ” And these are all indicators this tough job has gotten a lot tougher.”

Andrew also noted that the pandemic has made things tougher in courtrooms and hospitals which has also contributed to rising crime numbers.