In late December, Munir Awad, a 29-year-old Swede born in Lebanon, is currently detained -- along with three other men, including two Swedish citizens -- on suspicion of planning a December attack on the Jyllands-Posten daily which had published caricatures of the prophet Muhammad.
In an interview with the Dagens Nyheter (DN) newspaper, Benaouda said she first learned of Awad's arrest when she received a call from a journalist.
“I asked my daughter and when we looked for him, he wasn't anywhere to be found,” Benaouda told the newspaper.
She said that if the suspicions against Awad prove to be true, it would be surprising that her daughter didn't know anything.
Even though the couple don't currently live together, they have frequent contact, she explained.
Benaouda, who has previously said she had never come across any Muslim extremists, said it was possible her daughter did not know of the plot.
But she added she should have been suspicious about her son-in-law's plans.
"Safia says 'I don't get it and I don't know what he is up to'. And I should have known myself. How is it possible to hide such things to those close to you?," she told the paper.
Awad had also shared a Stockholm-area flat with one of two Swedes of Somali origin who were sent to jail in December for "planning terrorist crimes" in Somalia.
When Awad's former flatmate was arrested in June, Benaouda told her son-in-law "that he shouldn't mix with people who get arrested. But I didn't say more, because I don't have such a close relationship to him", she told DN.
At the same time, Benaouda added that extremists often keep their plans secret from relatives.
“Men who really are extremists mistrust society and vice-versa. And at the same time women become suspected by society because everyone thinks they know something,” she said.
Benaouda admitted as well that she was “completely clueless” about the trip Awad and her daughter took to Somalia in 2007, which her daughter had described at the time as a spontaneous side trip from the couple's Christmas break trip to Dubai.
“I don't understand myself why someone would want to travel to Somalia,” she said.
Awad has been imprisoned on two previous occasions, once in Ethiopia in 2007 and once in Pakistan in 2009. He also has unpaid debts registered with the Swedish Enforcement Agency (Kronofogden) because the Swedish foreign ministry paid for his trip home from Ethiopia following his release.
However, questions also remain as to how he paid for his trip home from Pakistan.
“I don't have any insight into their finances. But I know that my daughter doesn't have any money. She said that Munir paid,” said Benaouda.
Benaouda said she had received threats and not publicly spoken about her son-in-law's arrest to take the time to deal with the family crisis.
She condemned all forms of extremism in Islam, including Sweden's first suicide attack, carried out in December by an Iraqi-born Swede who killed only himself after sending a message saying he was acting in the name of Islam.
"There are no holy wars in Islam," Benaouda said.
"For me, the Stockholm suicide bomber is a criminal. I distance myself from all Islamic extremism. The use of violence is always unacceptable."