What type of gear do we have, here?
What type of squad are we?
What time of day is it? Weather? (This matters to me.)
In a relatively-optimal situation, smoke grenades would work wonders.
In a truly optimal situation, there are pieces of equipment now (helmets, specifically) that let you track sniper fire and pinpoint the location of where the shot was fired using the impact point and sound waves as recorded by a squad of multiple people. If we had that, we could find out where he was, and take him out ourselves.
Again, this is depending on the squad and the situation. We might have a sniper of our own, and there might be a building nearby we could take cover in, and head there under the cover of smoke grenades.