Israel has freed four Egyptian prisoners, in addition to two others who had already walked free, in a deal that secured last week's release from Egypt of Israeli citizen Ouda Tarabin who was convicted of spying.

Israel Prisons Authority spokeswoman Sivan Weizman says the four Egyptians were imprisoned for drug trafficking. One had served his full sentence while the others were released between two and six years early.

Weizman says the four were flown back to Egypt on Monday.

Tarabin, a Bedouin Arab, returned to his family last Thursday after serving a 15-year sentence in an Egyptian prison on charges of spying for Israel. The 34-year-old Tarabin had maintained he was innocent.

After his release, he referred to his incarceration as "when I was in a cemetery in Egypt."