Okoro, who leads the scorers' list with 16 goals, netted twice in the 15th and 85th minutes while Brazilian D'Silva nicely converted a free-kick in the 53rd minute in a one-sided encounter at the Salt Lake stadium.
With this win, which followed two reverses against JCT and Mahindra United respectively, the red and yellow brigade consolidated their position at the top of the league with 46 points from 20 matches.
Nigerian striker Okoro drew the first blood as he chested a diagonal aerial pass from Chandan Das
inside the box and gently pushed the ball past an advancing Indian Bank custodian Sebastian Netto.
East Bengal, who were on the prowl from the start, made the scoreline 2-0, converting a free-kick from just outside the opponent's box. Douglas, who missed the last match due to a double booking, showed his class as his left-footer found its way past the defence wall and swung into the net.
Not satisfied with a 2-0 margin, East Bengal continued their onslaught and reaped the fruit of their labour in the 85th minute when MalsawmTluanga paved way for Okoro to strike his second goal and the third for his team.
Earlier, both the teams observed a minute's silence before the match in memory of Krishanu Dey.
