SB 10.77.9

vīkṣya tat kadanaṁ svānāṁ
 nirūpya pura-rakṣaṇam
saubhaṁ ca śālva-rājaṁ ca
 dārukaṁ prāha keśavaḥ
Word for word: 
vīkṣya — seeing; tat — that; kadanam — destruction; svānām — of His own men; nirūpya — arranging; pura — of the city; rakṣaṇam — for protection; saubham — the vehicle Saubha; ca — and; śālva-rājam — the King of the Śālva province; ca — and; dārukam — to Dāruka, His chariot driver; prāha — spoke; keśavaḥ — Lord Kṛṣṇa.
Translation: 
[Śukadeva Gosvāmī continued:] After He arrived at Dvārakā and saw how His people were threatened with destruction, and also saw Śālva and his Saubha airship, Lord Keśava arranged for the city’s defense and then addressed Dāruka as follows.
Purport: 

Lord Kṛṣṇa placed Śrī Balarāma in a strategic position to guard the city, and He also appointed a special guard for Śrī Rukmiṇī and the other queens inside the palaces. According to Śrīla Viśvanātha Cakravartī, by a secret route special soldiers conveyed the queens to safety inside Dvārakā.