How is Odysseus threatened by the suitors when he is about to slaughter them?

After he has proven himself with the axeheads, Odysseus stands by the door and kills Antinoos with an arrow through the throat. The suitors look for weapons on the wall, but there are none. They promise death for Odysseus, but he reveals his identity and vows to exact vengeance. The suitors are intimidated, and Eurymakhos says that the dead Antinoos was their leader and coerced them into following him; if Odysseus spares the suitors, they will repay what they took from him.