Following the arrest of four radical Islamic extremists on Friday, French authorities have now halted five radical Islamic terror attacks in the first four months of 2019.

The four individuals arrested remain in custody and are said to have been plotting to murder French police officers. One of the group, who is under the age of 18, was previously sentenced for trying to join the Islamic State in Syria, France Soir reports.

Investigators say that the four men had already drawn up plans for the attacks and had wanted them to coincide with the beginning of the Islamic holy month of Ramadan which begins next month.

The plot joins four more that have been halted by French police this year, such as one that was stopped in March after the arrest of two 20-year-old men who were believed to have been plotting to attack a kindergarten, take some of the children and staff hostage, and then attack police officers who arrived on the scene.

Five Terror Attacks Thwarted by France This Year https://t.co/LTZRn3QXFM — Breitbart London (@BreitbartLondon) October 23, 2018

In mid-April, a 16-year-old was arrested on terrorist offences after investigators visited his home and found “tutorials detailing methods of terrorist action” along with pro-jihadist videos and searches for officials in the country’s domestic intelligence service, the DGSI.

The number of plots for 2019 could surpass the number of cases last year, which in October were said to number five, according to French interior minister Christophe Castaner.

While the plots uncovered this year mostly focus on the targeting of police and others, much larger and ambitious plots have been described by Islamic State detainee Jonathan Geffroy.

Last year, Geffroy claimed that the two most senior French Islamic State members, the Clain brothers, had plotted to not only commit mass shootings but to also cause an environmental catastrophe by attacking a nuclear power plant.

Since Geffroy’s testimony, both Fabien and his brother Jean-Michel have been killed in the Middle East.

Islamists Arrested Over Kindergarten Children Massacre Plot https://t.co/WtijadQTwZ — Breitbart London (@BreitbartLondon) April 4, 2019