CHICAGO — Two people were killed and at least 30 others were wounded in mass shootings in three states over the weekend, authorities said, stoking concerns that a spike in gun violence could continue into summer as coronavirus restrictions ease and more people are free to socialize.

The attacks took place late Friday or early Saturday in the Texas capital of Austin, Chicago and Savannah, Ga.

The attacks come amid an easing of COVID-19 pandemic restrictions in much of the country, including Chicago, which lifted many of its remaining safeguards on Friday. Many hoped that a spike in U.S. shootings and homicides last year was an aberration perhaps caused by pandemic-related stress amid a rise in gun ownership and debate over policing. But those rates are still higher than they were in pre-pandemic times, including in cities that refused to slash police spending following the death of George Floyd and those that made modest cuts.

“There was a hope this might simply be a statistical blip that would start to come down,” said Chuck Wexler, executive director of the Police Executive Research Forum. “That hasn’t happened. And that’s what really makes chiefs worry that we may be entering a new period where we will see a reversal of 20 years of declines in these crimes.”

Tracking ups and downs in crime is always complicated, but violent crime commonly increases in the summer months. Weekend evenings and early-morning hours also are common windows for shootings.

Many types of crime did decline in 2020 and have stayed lower this year, suggesting the pandemic and the activism and unrest spurred by the reaction to Floyd’s death didn’t lead to an overall spike in crime.

According to a database compiled by The Associated Press, USA Today and Northeastern University, only three mass shootings occurred at public places — the lowest total for that category in a decade — out of 19 total mass shootings in 2020.

The database tracks all mass killings including shootings, defined as four or more people dead not including the perpetrator.

According to that definition, there have been 17 mass killings, 16 of those shootings, already this year, said James Alan Fox, a criminologist and professor at Northeastern University.

The Gun Violence Archive, which monitors media and police reports to track gun violence, defines mass shootings as those involving four or more people who were shot, regardless of whether they died. Overall, according to its database, more than 8,700 people have died of gun violence in the U.S. this year.

The GVA also found that mass shootings spiked in 2020 to about 600, which was higher than in any of the previous six years it tracked the statistic. According to this year’s count, there have been at least 267 mass shootings in the U.S. so far, including the latest three overnight Friday into Saturday.

“It’s worrisome,” Fox said. “We have a blend of people beginning to get out and about in public. We have lots of divisiveness. And we have more guns and warm weather. It’s a potentially deadly mix.”