Washington, May 16 (IANS): Police departments in New York City and other large metro areas across the US are bulking up patrols and implementing new tactics to prepare for what they say could be a "violent summer", according to a media report.

States lifting Covid-19 restrictions and more people out in public spaces in warmer weather increase the likelihood of more shootings, as well as less-serious crimes, officials were quoted as saying The Wall Street Journal (WSJ) report on Saturday.

Many crimes, including violent ones, normally rise in summer, Xinhua news agency reported.

Gun purchases also rose during the pandemic and cities have seen an increase in guns being used in crimes, according to the WSJ report.

Shootings and homicides in big US cities are up this year again after rising last year.

In the last three months of 2020, homicides rose 32.2 per cent in cities with a population of at least one million, according to the Federal Bureau of Investigation's Quarterly Uniform Crime Report.

In New York City, the number of homicides has reached 146 for the year so far, an increase of 27 percent from 115 during the same period in 2020.

In Dallas, police have counted 75 homicides this year, up from 58 during the same period last year.

Chicago police have recorded 195 homicides, up from 160 in the year-ago period.

"We're coming out of the pandemic, life is starting again and more people are going to be out on the street," director of public safety James Shea of the Jersey City, New Jersey, was quoted by the WSJ as saying.

So far, over 30 per cent of Americans have been fully vaccinated against Covid-19, mask mandates are being loosened at federal, state and city levels, and local governments are preparing to open economies to wider spectrums.

New York City is to fully reopen its economy on July 1.