2 Muslim girls vanish, feared to have joined ISIS in Syria

In an interview with CNN, mother of one of the missing girls Rahma Adan explained that her daughter , 20-yr-old Tawfiqua and her friend Salwa Abdulla vanished earlier this month.

Their families say the two girls went to Tawfiqua's home in the Kenyan capital, Nairobi, on May 13, after their day's lessons at a nearby Islamic school.

A short time later, Tawfiqua left the house to see Salwa off, but never returned. The pair hasn't been seen since.

The disappearance sparked a desperate search by both families, but there was no trace of the friends.

Four days later, they received a shocking message -- thought to have been sent by Tawfiqua to her cousin -- which read in part: "Assalam aleykum cuz, how are you? Am now in Syria ... Tell everyone not to look for me am doing very fine."

Rahma says both families were devastated by the unexpected news.

"When I received the message, I was shocked," she told CNN. "I fainted, and the entire family, who were with me, was also shocked and cried."

Tawfiqua and Salwa, who were both university students, are described by their families and friends as kind, quiet and devout Muslims.

"When she has free time, she always reads the Quran, she doesn't watch movies," Rahma says, unfolding the maroon and gold mat her daughter used to pray on. "She loves her religion, as a Muslim, she loves her religion."

As days become weeks, there is still no firm confirmation on the young women's whereabouts.

Rahma is confused as to how -- if indeed she is in Syria -- Tawfiqua managed to leave the country without an identity card or a passport.

Kenyan police say they have launched investigations into the case, but also wonder how the two left the country.

But if they have gone overseas to join ISIS, Tawfiqua and Salwa aren't the first to have made the journey: In March, Kenyan police arrested four young women trying to cross the border into Somalia without proper travel documents.

The four have been charged in a Mombasa court with being members of Somali insurgent group Al-Shabaab. They deny the charges.

Police and some religious leaders say a growing number of young Kenyans are sneaking across the border to join foreign terror groups.

Security experts say Kenyans form the largest number of foreign recruits to al Qaeda-linked Somali insurgent group Al-Shabaab. They say extremist preachers prey on young Muslims who are searching for identity and a sense of belonging, and radicalize them.

Rahma Adan says that although she finds it difficult to believe, there is a possibility her daughter was radicalized.

"I don't know," she admits. "Maybe it is Satan who has changed her mind. Maybe people came and told her something -- told her wrong stories, and tell her maybe this is good."

Asked if she has a message for her missing daughter, Rahma issues a desperate plea: "I beg her to come back to me. Because as a mother, I am hurting."