Photographer Houssam Mohammed and Salma al-Shimi were arrested on Monday and referred to the prosecution after the shoot at the Saqqara necropolis, 30 kilometres (20 miles) south of Cairo, in which Shimi appeared in ancient Egyptian costume.
Shimi, who boasts thousands of followers on Instagram, had posted photographs last week at the foot of the 4,700-year-old Step Pyramid of Djoser.
Rumours quickly spread that she had been detained for wearing outfits that betrayed Egypt's ancient heritage and had broken the rules set by the antiquities ministry for photo shoots.
The judicial source said the pair were accused of "taking photos without authorisation in the Saqqara archaeological site" and released on bail of 500 Egyptian pounds ($32) each pending the results of an investigation.
According to a statement on the tourism ministry's Facebook page, Mostafa Waziri, secretary-general of Egypt's Supreme Council of Antiquities, had asked for the matter to be referred to the prosecutor, deeming the photos "inappropriate".
"All those found guilty of harming archaeological sites and Egyptian civilisation will be punished," Waziri was quoted as saying in the statement.
The matter has sparked controversy on social media, with some users expressing disbelief and outrage.
"Is there really a ban on taking photographs in archaeological zones, even pictures that are not indecent but completely normal?" one user asked.
In recent months, Egyptian courts have handed down jail sentences against a dozen social media influencers for sharing content judges deemed offensive.
In December 2018, images of a naked couple embracing at the top of the Great Pyramid of Cheops prompted a media outcry.
The authorities arrested a camel owner and a young female guide for helping the couple to gain access to the site.
Follow us on Facebook, Twitter and Instagram to stay connected
Follow the Middle East's top stories in English at The New Arab on Google News
