The foreigners, two from Thailand and three from China, are engineers and were present inside the plant at the time of the blast, the state's Labour and Employees' Insurance Department Minister Bijayshree Routray told reporters here.
He said the government was not in a position to confirm the exact number of people who died or were injured in the mishap as a probe was underway.
"The labour system in the plant is full of flaws. Whereabouts of the five foreigners, present inside the plant, are not known," he said.
The explosion occurred Nov 13 at about 10 a.m. in blast furnace No. two of Bhushan Steel Ltd plant in Narendrapur village, about 150 km from the state capital Bhubaneswar. Plant officials claimed one worker died and 15 others were injured.
The state government began a probe after allegations that the company concealed information regarding the number of dead and injured.
Although the area authorities sealed the blast furnace after the incident, and arrested three senior company officials for negligence, workers, trade union activists and politicians continued their protest near the plant Saturday accusing the company and the government of concealing information.
Several women broke down while searching for their relatives who are missing after the mishap.
"We suspect that more than 100 people were killed in the blast," Bishnu Mohanty, National Vice-president of Centre of Indian Trade Unions, said. The company has however denied the allegation.
The steel plant of Bhushan Steel Ltd which was commissioned in 2006 manufactures pig iron, billets, slabs and hot-rolled steel coil. It has an annual output of about 3.1 million tonnes.
The company had announced increasing the capacity to six million tonnes by the end of this year. It was commissioning the second blast furnace as part of its expansion work.
At least 98 people in the same plant have died in accidents since 2005, officials said.
--IANS (Posted on 16-11-2013)