Sambo made this known in a statement made available to newsmen in Lagos on Saturday.
He spoke while on inspection tour of the project in Port Harcourt, Rivers.
Sambo said China Civil Engineering and Construction Company (CCEC), the contractor handling the rehabilitation and reconstruction of the project, had complained of attacks on its workers along the Abia State axis.
“I am very displeased by these acts, and I condemned it in strong terms.
“In the history of Nigeria, no administration has invested more in rail infrastructure like the present administration of President Muhammadu Buhari.
“I call on the media and the judiciary to collaborate with the Ministry to ensure that these economic saboteurs are not only exposed but prosecuted and sentenced speedily to serve as deterrent to others,” he said.
The minister dismissed as fake, news being circulated that funds meant for the Eastern rail line was diverted to other projects.
“The progress made so far is from the 15 per cent of the counterpart funding by Nigeria while the 85 per cent to be provided by foreign parterners is still negotiated,” Sambo said.