"A total of 23 fishermen belonging to Kanyakumari district in Tamil Nadu went to the coastal waters of UAE (in 2014) for fishing, accompanied by two Arabs. One Arab went missing and all the Tamil fishermen were arrested," he said in separate letters to Modi and Swaraj.
Stating that investigation into their whereabouts had been going on for the past two years, Vaiko said UAE officials found the fishermen "innocent" and "arrayed" them as eyewitnesses.
Though the fishermen were not jailed, they were confined to rooms, almost like a "house arrest" and were struggling to meet their daily needs, he said.
He urged Modi and Swaraj to extend all possible help to save the fishermen.
"The families are eagerly anticipating help from the Indian Government and strong action from the Prime Minister's Office...," he said.