diff --git a/libcontainer/container_linux.go b/libcontainer/container_linux.go
index 79f6d33c5..ce62ea481 100644
--- a/libcontainer/container_linux.go
+++ b/libcontainer/container_linux.go
@@ -837,13 +837,19 @@ func (c *linuxContainer) handleCriuConfigurationFile(rpcOpts *criurpc.CriuOpts)
 }
 
 func (c *linuxContainer) criuSupportsExtNS(t configs.NamespaceType) bool {
+	var minVersion int
 	switch t {
 	case configs.NEWNET:
 		// CRIU supports different external namespace with different released CRIU versions.
 		// For network namespaces to work we need at least criu 3.11.0 => 31100.
-		return c.checkCriuVersion(31100) == nil
+		minVersion = 31100
+	case configs.NEWPID:
+		// For PID namespaces criu 31500 is needed.
+		minVersion = 31500
+	default:
+		return false
 	}
-	return false
+	return c.checkCriuVersion(minVersion) == nil
 }
 
 func (c *linuxContainer) criuNsToKey(t configs.NamespaceType) string {
@@ -979,6 +985,11 @@ func (c *linuxContainer) Checkpoint(criuOpts *CriuOpts) error {
 		return err
 	}
 
+	// Same for possible external PID namespaces
+	if err := c.handleCheckpointingExternalNamespaces(&rpcOpts, configs.NEWPID); err != nil {
+		return err
+	}
+
 	// CRIU can use cgroup freezer; when rpcOpts.FreezeCgroup
 	// is not set, CRIU uses ptrace() to pause the processes.
 	// Note cgroup v2 freezer is only supported since CRIU release 3.14.
@@ -1304,6 +1315,11 @@ func (c *linuxContainer) Restore(process *Process, criuOpts *CriuOpts) error {
 		return err
 	}
 
+	// Same for PID namespaces.
+	if err := c.handleRestoringExternalNamespaces(req.Opts, &extraFiles, configs.NEWPID); err != nil {
+		return err
+	}
+
 	// This will modify the rootfs of the container in the same way runc
 	// modifies the container during initial creation.
 	if err := c.prepareCriuRestoreMounts(c.config.Mounts); err != nil {