Story highlights "I wanna kill . . . them in thousands," one of the men allegedly wrote to an undercover agent

One of the men has pleaded guilty

Washington (CNN) Federal officials on Friday unsealed charges against three men accused of a thwarted plot to attack concert venues and landmarks around New York City in 2016, according to court documents -- a case that comes on the heels of a mass shooting at a concert in Las Vegas.

The three men allegedly used internet messaging applications to plot bombings and shootings in Times Square, the New York subway and concerts during Ramadan last year, according to a news release on the unsealed court documents from the acting US attorney for the Southern District of New York.

Charged in the case are Abdulrahman El Bahnasawy, 19, a Canadian citizen; Talha Haroon, 19, a US citizen living in Pakistan; and Russell Salic, 37, a Philippines citizen, the release said. According to prosecutors, all three have been arrested and El Bahnasawy has already pleaded guilty following his May 2016 arrest. Haroon and Salic have been arrested overseas, and the US is seeking to have them extradited to stand trial here.

El Bahnasawy allegedly traveled to New Jersey to carry out the attacks, purchased bomb-making materials and helped rent a cabin for building the devices, the news release said. Haroon is alleged to have planned to travel from Pakistan to New York to help and met with bomb experts in Pakistan. Salic is charged with wiring money from the Philippines to further the plot.

El Bahnasawy and Haroon allegedly communicated with an undercover officer posing as an ISIS supporter about their plot and declared their allegiance to ISIS in the communications, according to investigators.

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