SB 10.52.14

so ’pi dagdhāv iti mṛṣā
 manvāno bala-keśavau
balam ākṛṣya su-mahan
 magadhān māgadho yayau
Word for word: 
saḥ — he; api — further; dagdhau — both burned in the fire; iti — thus; mṛṣā — falsely; manvānaḥ — thinking; bala-keśavau — Balarāma and Kṛṣṇa; balam — his force; ākṛṣya — pulling back; su-mahat — huge; magadhān — to the kingdom of the Magadhas; māgadhaḥ — the King of the Magadhas; yayau — went.
Translation: 
Jarāsandha, moreover, mistakenly thought that Balarāma and Keśava had burned to death in the fire. Thus he withdrew his vast military force and returned to the Magadha kingdom.