The residents of the U.S. state of Colorado gathered at the Boulder Police Department and the Boulder Kings Soopers store on March 23 to mourn the victims of mass shooting that took place at a King Soopers store on Monday.

The shooting killed 10 people ranging in age from 20 to 65 and including an 11-year-veteran of the Boulder police force identified Officer Eric Talley. Ahmad Al Aliwi Alissa, the suspect has been charged with 10 counts of first-degree murder. According to the court documents, the 21-year-old man purchased an assault rifle less than a week before the attack on March 22.

U.S. President Joe Biden on Tuesday called on the Congress to tighten the nation's gun laws.

Flowers cover a police car parked outside the Boulder Police Department in honor of Officer Eric Talley, who was one of the 10 people killed during a mass shooting at a King Soopers' store in Boulder, Colorado, March 23, 2021. /CFP

Employees of King Soopers place flower bouquets with messages of condolences for the victims of mass shooting at a King Soopers store at a makeshift memorial, March 23, 2021. /CFP

A sign from residents of south Boulder stands amid bouquets of flowers at the parking lot where a mass shooting took place in a King Soopers store, March 23, 2021. /CFP

Bouquets line a fence put up at the parking lot where a mass shooting took place the day before in a King Soopers store, March 23, 2021. /CFP