Depends, usual lethal radius between 5-25m, some shrapnel might be lethal beyond that. If you start driving slowly and accelerate moderately you might geht caught by some shrapnel.

Anyways, the thief would definitely notice the explosion. You would notice several blocks away.

Possibly without even knowing

Not for long though. I give it about 3-5 seconds until the thief would notice. Probably the last thing they will ever notice.