Report them using the in-game reporting feature if there is one, faling that use the link below, although it'll take you a while to report 250 people!
Customer Service - 1-800-345-SONY (7669)
Account & billing Support -1-877-971-SONY (7669)
Available Mon to Fri 8am - 8pm PST
Live Chat Available Mon-Sat 6am-10pm PST & Sun 6am-8pm PST
More than likely they are laughable wannabe hackers trying to hack the PSN all over again like the April 20, 2011 outage which won't happen again because there are other people going to report them. Blackmailing 250 hackers won't do anything good. Best bet is to report the ringleader of the masses, nascar12345678.
Playstation Telephone Hours: Monday-Friday 8:00am-8:00pm PST (Closed on Saturdays & Sundays)
Customer Service - 1-800-345-7669
Account and Billing Support - 1-877-971-7669
Sony Rewards - 1-888-715-7669