cannot set local variable in the RETURNING clause of INSERT ... RETURNING

CREATE TABLE `tbl2` (

  `col1` int(11) DEFAULT NULL,

  `col2` int(11) DEFAULT NULL,

  `col3` int(11) NOT NULL AUTO_INCREMENT,

  PRIMARY KEY (`col3`)

);

CREATE PROCEDURE test_proc(

	IN col1_param INT,

	IN col2_param INT

)

BEGIN

	DECLARE loc_var INT;

	INSERT INTO tbl1 (col1, col2) VALUES (1, 2) RETURNING loc_var := col3;

	SELECT loc_var;

END

You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near ':= col3;

	SELECT loc_var;

END' at line 7

CREATE PROCEDURE test_proc(

	IN col1_param INT,

	IN col2_param INT

)

BEGIN

	INSERT INTO tbl1 (col1, col2) VALUES (1, 2) RETURNING @ses_var := col3;

	SELECT @ses_var;

END