(CNN) -- Four women were detained by traffic police in two Saudi Arabian cities this week for defying the Kingdom's driving ban, according to all the women stopped.
In the Red Sea port city of Jeddah Thursday, two women, Sahar Naseef and Tamador Alyami, were stopped by police after being spotted in a car on one of the city's main thoroughfares.
Alyami, who's been an avid supporter of a two-month-old campaign seeking to gain the right to drive for women in Saudi Arabia, told CNN she and Naseef were hoping to get caught.
"We did go driving on a main street where we know there's a lot of traffic police," explained Alyami, who was in the passenger seat.
"We're just trying to push and see how far can we go with this," said Alyami, "because two women yesterday were caught by police and detained for 10 hours. Today, in a different city it was totally different. We were caught and stopped for only two hours."
The woman who drove the car, Naseef, told CNN she was so convinced she and Alyami would spend the night in jail, she even packed a toothbrush, some shampoo and an extra set of clothing.
For Alyami, an author and columnist who's driven herself around Jeddah five times now, getting behind the wheel is no longer enough in an extraordinary campaign of civil disobedience that has seen dozens of women taking to the streets since October.
"We're asking girls in different regions to go out," she said, "because we're trying to see if police in different regions react differently to cases of women driving."
According to Naseef and Alyami, the traffic police officer who pulled them over was very kind to them and even supportive of their cause. They said he told them that due to protocol, he had to call for backup, and they were soon surrounded by several more police cars. In the end, Naseef had to sign a pledge not to drive again in the presence of a male relative before the women could be released.
One day earlier in the country's capital, Riyadh, which is in a far more conservative part of the country, two other women described a far more difficult experience after being caught driving.
Azza Al-Shamasi and Bareah Alzubeedy told CNN they were detained at a Riyadh police station for more than 10 hours after being caught and pulled over by traffic police.
Al-Shamasi, who was driving, said when they first started driving down one of Riyadh's main streets, many male drivers around them were giving them signs of support. Half an hour later, after a traffic police officer spotted them, they were pulled over.
"We were then surrounded by six cop cars, and the people who stopped us were quite rude," said Al-Shamasi.
According to Al-Shamasi, despite the fact that her husband came to the police station shortly after she was taken there, it still took at least eight more hours before she was released into his custody.
Alzubeedy explained they were not looking to attract the police's attention, just simply doing what they should be able to do.
"Freedom of movement is a right," said Alzubeedy, a human rights activist. "This is a right for women here. There's no law that bars women from driving in Saudi Arabia, and I hope more women will go out and drive."
Despite repeated attempts, CNN was unable to reach Saudi Arabia's Interior Ministry for comment.
The issue of women driving is a particularly sensitive and controversial one in Saudi Arabia, the last country on Earth where females don't have that right. In recent years, though, more women have challenged the government, urging officials to overturn the ban and taking to streets in remarkable displays of civil disobedience. Although women are not allowed to drive in the ultraconservative Kingdom, there is, in fact, no law barring them from doing so. But religious edicts are often interpreted to enforce the prohibition.
In May 2011, Manal Al-Sharif was jailed for more than a week after posting a video of herself driving in Saudi Arabia online. She quickly became a hero to many and inspired dozens of women to drive throughout the streets of various cities in June of that year.
More recently, in September, a website for the October 26 Women's Driving Campaign launched, and within a few weeks, tens of thousands had signed an online petition calling for an end to the driving ban for women in Saudi Arabia. As October 26 approached, numerous women filmed themselves driving in the conservative Kingdom and uploaded those clips to sites like YouTube.
In the weeks leading up to October 26, one Saudi cleric gave an interview in which he warned that Saudi women who drove risked damaging their ovaries. On October 24, the country's Interior Ministry issued a statement telling women to stay off the streets.
Despite strong opposition by conservative quarters in the Kingdom, where a puritanical strain of Islam is practiced, October 26 saw dozens of women taking to the streets and driving. The campaign's backers insist the movement is ongoing and has been a success thus far, while its critics say it has failed.
In early December, two of Saudi Arabia's best-known female advocates for lifting the ban on women driving were also detained after being caught behind the wheel in the country's capital. Aziza Al-Yousef, who was driving the car, and her passenger, Eman Al-Nafjan, told CNN they were pulled over and spent a few hours at a police station in Riyadh until being released into the custody of their respective husbands.