Around 200,000 'harkis' fought against fellow Algerians in the 1954-1962 war, and tens of thousands of them were killed after the French withdrawal.
As a part of this exercise, several activities including coordinated manoeuvring, communication procedures and steam past were undertaken between the Indian and Algerian warships.
UNEP said in a statement that the eradication of leaded petrol would "prevent more than 1.2 million premature deaths per year.
Algeria formally announced the decision on Tuesday, citing a series of alleged hostile acts.
There was no official explanation of the high death toll among soldiers but photos in Algerian media showed soldiers in their army fatigues with no protective firefighting clothing.
Algeria joins a string of countries to be hit by major blazes in recent weeks, including Greece, Turkey, Cyprus and the western United States.
Authorities have tightened the screws on the Hirak protest movement in recent weeks, and police arrested a politician and journalist who are prominent opposition figures in the run-up to the voting.
The warrants come as Algeria's anti-government protesters, the Hirak movement, are boosting weekly rallies ahead of June elections.