Nine mass shootings occurred across the United States over the weekend, bringing the total to more than 400 this year, according to a national website that tracks firearm deaths and injuries.

The nine mass shootings led to at least four deaths and 35 injuries as of Sunday, according to the latest data from the Gun Violence Archive, which defines a mass shooting as an event with at least four victims either injured or killed, not including the shooter.

The website recorded 404 mass shootings as of Sunday since the start of 2023, which left at least 453 people dead, according to the data, which are collected or validated from 7,500 sources daily.

Among those killed were some 161 children under age 12, and another nearly 400 children had been injured in mass shootings so far this year, according to the anti-gun violence group.

The number of mass shootings was 9 percent up from a year earlier. As of July 23, 2022, there were 365 mass shootings, and that year saw a total of 647 mass shootings across the country.

The increase confirmed a rising trend of mass shootings in the United States.

In 2016, the country reported 383 mass shootings. The last three years all surpassed 600, with 2021 registering the largest number — 690 mass shootings, according to the Gun Violence Archive.