A sequel was indeed announced. But obviously nothing ever came of it.
"Rumours about a sequel to Jericho were confirmed when Clive Barker had announced his intention to make a sequel to the game. [19] In an interview, Barker let slip that plot details include "an aircraft carrier in the middle of the ocean with exactly 666 children in its hold", and will reveal the fate of the remaining Jericho members, especially Ross, following the death of the Firstborn."