Write SQL query to solve given problem: How many Japanese suppliers have their accounts in debt?. Keep the solution inside sql tag ```sql [SQL-Query] ```
SELECT COUNT(T1.s_suppkey) FROM supplier AS T1 INNER JOIN nation AS T2 ON T1.s_nationkey = T2.n_nationkey WHERE T1.s_acctbal < 0 AND T2.n_name = 'JAPAN'