Will clung to the hope that his call would be answered. He tapped incessantly on the communicator in his hand; beeps erupted from its internal workings, sounds that could give away his presence. The sound of footsteps echoed in the closet where he knelt; they were getting closer. He tried to swallow the fear that seemed to be choking him.
He put his ear to the door, listening for a sign that his pursuers might be close to finding him. The footsteps stopped. Will could hear the creaking of a door opening, and muffled voices. They were close, perhaps only meters away.
A distorted crackle began to emanate from his earpiece, and then the sound he was hoping for, “Tango One, are you receiving?”

It was also hard for me to figure out where he is in relation to his pursuers. Are they both in this closet? If footsteps echo within the closet, that, in my mind, makes me think someone is in there with him.

"listening for a sign that his pursuers might be close to finding him..."
Drop the "to finding him." All we need to know is they're pursuing him, and of course we'll figure they're trying to find him.

"A distorted crackle began to emanate..."
Possible edit: "A crackle emanated from from his earpiece," or "His earpiece crackled."

The last sentence needs to be chopped in two with a period.
"His pursuers had heard him. It was now or never."

Lastly, you use "sounds" or "sound of" a lot in such a short space. Perhaps try to bring in verbs or nouns that imply sound. You don't need to say, "The sound of footsteps." You can just say "Footsteps echoed..."