PERUGIA, Italy — An Italian appeals court on Saturday heard witnesses brought in by the defense of Amanda Knox to refute testimony that placed the American student near the crime scene the night her British roommate was killed.

Knox was convicted of murdering Meredith Kercher in the apartment they shared as exchange students in Perugia, and sentenced to 26 years in prison. Her co-defendant and ex-boyfriend Raffaele Sollecito was also convicted and sentenced to 25 years.

They both deny wrongdoing and have appealed the 2009 verdict.

During the first trial, a homeless man, Antonio Curatolo, testified that he had seen Knox and Sollecito in a piazza near the house from about 9:30 p.m. to shortly before midnight on the night Kercher was killed, Nov. 1, 2007. Curatolo said at the time that he was certain because he also remembered seeing buses and other students in the piazza waiting to board buses to go to discos around town.

The defense wanted to show that Curatolo, a witness for the prosecution, is unreliable given he was wrong on the activity in the piazza that night.

Saturday's six witnesses included some operators of shuttle bus services that run from the piazza in question to discos on Perugia's outskirts, as well as people doing work for two discos.

The witnesses said shuttle bus services were not on that night. A woman working for one of the discos that normally uses the shuttle bus said her night club was closed the night of Nov. 1.

"I'm certain because discos focus on Halloween, which is a big draw. It's like New Year's Eve," said Rita Pucciarini, who at the time of the murder worked for the Red Zone disco. "There were no buses."

Nov. 1 is also a public holiday in Italy.

Luciano Ghirga, a lawyer for Knox, said the testimony "removes the two from the scene of the crime." But the prosecution maintained the witness testimonies were inconclusive.

Prosecutor Manuela Comodi called the testimony "useless," saying there are other discos in Perugia and other bus shuttle services whose operators had not been heard.

A lawyer for the Kercher family, Francesco Maresca, noted the testimony said nothing of the public buses that pass through the piazza. "I remain convinced of the reliability of this witness," he told reporters during a break in the session.

Curatolo is expected to take the witness stand again in the next hearing, on March 26. In a blow to the prosecution, Curatolo was recently convicted and arrested on an unrelated drug charge, news reports and officials said.

Knox said she spent the night at Sollecito's house, watching a movie, smoking pot and having sex.