diff --git a/src/safeposix/syscalls/sys_calls.rs b/src/safeposix/syscalls/sys_calls.rs
index 10be5122..1e78bbdc 100644
--- a/src/safeposix/syscalls/sys_calls.rs
+++ b/src/safeposix/syscalls/sys_calls.rs
@@ -773,10 +773,13 @@ impl Cage {
             return syscall_error(Errno::EINVAL, "sigkill", "Invalid cage id.");
         }
 
+
         if let Some(cage) = interface::cagetable_getref_opt(cage_id as u64) {
+            let threadid = cage.main_threadid.load(interface::RustAtomicOrdering::Relaxed);
+            if threadid == 0 { return syscall_error(Errno::ESRCH, "kill", "Target cage does not exist"); }
+            
             interface::lind_threadkill(
-                cage.main_threadid
-                    .load(interface::RustAtomicOrdering::Relaxed),
+                threadid,
                 sig,
             );
             return 0;