সীতয়ারাধিতো বহ্নিশ্ছায়া-সীতামজীজনৎ ।
তাং জহার দশগ্রীবঃ সীতা বহ্নিপুরং গতা ॥ ২১১ ॥
sitaya-by mother Sita; aradhitah-being called for; vahnih-the fire-god; chaya-sitam-the illusory form of mother Sita; ajijanat-created; tam-her; jahara-kidnapped; dasa-grivah-the ten-faced Ravana; sita-mother Sita; vahni-puram-to the abode of the fire-god; gata-departed; pariksa-samaye-at the time of testing; vahnim-the fire; chaya-sita-the illusory form of Sita; vivesa-entered; sa-she; vahnih-the fire-god; sitam-the original mother Sita; samaniya-bringing back; tat-purastat-in His presence; aninayat-brought back.
"When he was petitioned by mother Sita, the fire-god, Agni, brought forth an illusory form of Sita, and Ravana, who had ten heads, kidnapped the false Sita. The original Sita then went to the abode of the fire-god. When Lord Ramacandra tested the body of Sita, it was the false, illusory Sita that entered the fire. At that time the fire-god brought the original Sita from his abode and delivered her to Lord Ramacandra."
These two verses are taken from the Kurma Purana.