At least six Indian nationals were abducted by unknown armed men in Baghlan province of Afghanistan on Sunday, media reports said.
Another official, however, said the timing of the incident was "significant, given that India and China recently announced they would work together in infrastructure projects in the country".
The bomb went off at the Yaqoubi mosque in the eastern Khost province of Afghanistan at around 2:30 p.m. while people were gathered there for afternoon prayer and to register to vote in the country's October long-delayed parliamentary elections, according to Basir Bina of the provincial police force.
The engineers were working for Da Afghanistan Breshna Sherkat (DABS), which operates stations generating power, Indian officials in Kabul said. An Indian official revealed that more than 150 technical experts and engineers are now deployed across Afghanistan on different projects.
The foreign ministry in New Delhi said it was in touch with Afghan authorities and was ascertaining details of the incident.More news: Air France In Trouble
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According to reports, security officials in Afghanistan are now working with local tribal elders as rescue operation is underway to trace the seven engineers abducted by the suspected Taliban gunmen. However, no group has claimed responsibility for the abduction so far.
Nemati added that when the Taliban was contacted, the terrorist group said that it kidnapped the seven people on the assumption that they were employees of the government of Afghanistan.
Baghlan Governor had on Saturday said the terror group had abducted the Indian engineers and their driver, believing they were government employees. In 2016, an Indian aid worker, Judith D'Souza, was abducted in Kabul and was released 40 days later.
RPG Enterprises chairman Harsh Goenka tweeted an appeal to external affairs minister Sushma Swaraj and her ministry to "help rescue 7 of our managers from the kidnapping in Afghanistan".