GREENBURGH, N.Y. (AP) -- A man who was one of the last people to see an Indiana University student before she vanished in 2011 says the student's parents are harassing him and his friends.

Corey Rossman told The Journal News of Westchester, N.Y. ( http://lohud.us/16Wb0UY ) that he has cooperated fully with police investigators. However, he said Lauren Spierer's parents have been harassing him and his friends.

"It's inappropriate the way they're harassing people that are also victims in this case," Rossman said Thursday. "We've done nothing wrong. If we'd done something wrong, we would have been arrested already."

Spierer was 20 when she vanished on June 3, 2011, after a night of partying with friends in Bloomington.

The Journal News reports that Rossman was with Spierer in the hours before she disappeared. He accompanied Spierer to a bar and then to her off-campus apartment, where another student punched him in the face.

A surveillance video in that apartment complex showed Rossman then helping an unsteady Spierer out of the building after being punched.

His lawyer, Carl Saltzman, later said Rossman had lost memory of the night's events. But Rossman said Thursday that he has never said that.

"You're taking statements that were said by my lawyer. I never said I did or didn't," he said.

Charlene and Robert Spierer have accused Rossman and other "persons of interest" of withholding information from police and have called on all of them to submit to police-administered polygraph tests.

Charlene Spierer said Thursday that she and her husband did arrange to meet Rossman's lawyer in Bloomington in October 2011, but the lawyer failed to show up for the appointment.

She scoffed at Rossman's claims that she and her husband have harassed him.

"Rob and I have never spoken to Corey Rossman," Spierer said. "The private investigators have never spoken to Corey. So I don't know how it is we're harassing him other than asking him to talk to the Bloomington police department. All of them," she said.