BERLIN — German lawmakers investigating a string of far-right killings said Monday there appeared to have been a coverup by officials who withheld information on the authorities’ contacts with neo-Nazis linked to the case.

Members of the cross-party committee set up to investigate 10 suspected neo-Nazi killings between 2000 and 2007 have previously voiced frustration that law enforcement agencies appeared to have held back evidence — and, in at least two instances, shredded material.

Their anger reached another peak after revelations last week that a mole in the far-right scene gave Berlin police information in 2002 that could have led to the arrest of the three main suspects in the killings.

‘‘That the [parliamentary] investigation committee wasn’t informed seems to have been intentional,’’ said Sebastian Edathy, its chairman.

Fellow lawmaker Hans-Christian Stroebele went further, accusing security officials in the state of Berlin of deliberately lying to lawmakers.

‘‘They didn’t tell us anything,” Stroebele told rbb-Inforadio. ‘‘On the contrary, we were told they had nothing. That can only be described as a lie.’’