The Dutch public prosecutor's office opened an investigation on Saturday into a suspected terror plot in the Netherlands. The counterterrorism Special Intervention Service (DSI) and police initially arrested four people in Rotterdam who were suspected of plotting a "terrorist crime," police said.

Police in the western German city of Mainz later detained a fifth suspect, a 26-year-old Syrian man with no prior criminal record, after searching the apartment where he was found. Police said they sought the suspect's arrest after receiving an extradition request from Dutch authorities.

"He is strongly suspected of taking part in the preparation for an attack in the Netherlands," police said.

Details unknown

Dutch officers carried out searches at the locations where the four suspects were detained, according to police. Details of any evidence seized were not given and no further information on the suspects was provided by authorities.

"Investigations will continue in the coming days, with the emphasis on further investigation of the nature and scale of the terrorist threat."

Police in both countries did not immediately reveal details of the alleged planned attack.

Chronology: Terror plots in Germany Leipzig, October 2016 Police in Leipzig arrested 22-year-old Syrian refugee Jaber al-Bakr after a two-day manhunt following the discovery of explosives and other bomb-making equipment at his apartment in Chemnitz. He was suspected of plotting to attack a Berlin airport. Two days later, he hanged himself in his prison cell.

Chronology: Terror plots in Germany Ansbach, July 2016 In July, the "Islamic State" (IS) claimed responsibility for two attacks carried out by asylum seekers. 15 people were injured in a crowded wine bar next to the entrance to a music festival in the Bavarian town of Ansbach after a rejected Syrian asylum seeker detonated an explosive device. The man killed himself in the attack.

Chronology: Terror plots in Germany Würzburg, July 2016 A 17-year-old asylum seeker wielding an axe and a knife went on a rampage on a regional train near Würzburg, seriously injuring four members of a tourist family from Hong Kong and a passer-by. The attacker was shot dead by police. German authorities said the teenager was believed to be a "lone wolf" inspired by the IS, but without being a member of the network.

Chronology: Terror plots in Germany Düsseldorf, May 2016 Three suspected members of the "Islamic State" terror network were arrested in the German states of North Rhine-Westphalia, Brandenburg and Baden Württemberg. Authorities say two of the men planned to blow themselves up in downtown Düsseldorf, while the other attacker and a fourth jihadist arrested in France planned to target pedestrians with guns and explosive devices.

Chronology: Terror plots in Germany Essen, April 2016 Police arrested three people over a bomb blast that injured three people in a Sikh temple in Essen. The bomb detonated after a wedding party, blowing out windows and destroying a part of the building's exterior. A 16-year-old suspect turned himself in after police showed footage of the attack from a surveillance camera and special police units arrested another young suspect in his parents' home.

Chronology: Terror plots in Germany Hanover, February 2016 German-Moroccan Safia S. is charged with stabbing a police officer at the main train station in the northern city of Hanover. The 16-year-old girl is suspected of having been "motivated by members of the Islamic State group in Syria to commit this act," chief prosecutor Simon Heinrichs said.

Chronology: Terror plots in Germany Berlin, February 2016 In separate raids across the country, police arrested three Algerians suspected of links to the "Islamic State" militant group and of having planned a terrorist attack in Berlin. The Berlin prosecutor's office said prosecutors were aware of a "concrete" plan to target the capital.

Chronology: Terror plots in Germany Oberursel, April 2015 The Eschborn-Frankfurt City loop bike race was called off after German police discovered it may have been the target of an Islamist terror attack. A 35-year-old German with a Turkish background and his 34-year-old wife were arrested on suspicion of planning the attack. Police found bomb-making materials in their home near the bike route. Author: Dagmar Breitenbach



Previous incidents in the Netherlands

In September, Dutch police said they foiled a "major terrorist attack" on civilians, with seven people from one terror cell arrested in Arnhem near the German border. Investigators said they found a large quantity of bomb-making materials, including fertilizer likely to be used in a car bomb, following the arrests.

At the end of August, police in Amsterdam's central station shot a 19-year-old Afghan man, Jawed S., after he stabbed two American tourists. City officials said the teen, who had a German residence permit, had a "terrorist" motive.

In June, two terror suspects aged 22 and 28 were arrested for planning to carry out attacks including at an iconic bridge in Rotterdam and in France, prosecutors said.

The last major attack in the Netherlands was the killing by a Muslim radical of Dutch anti-Islam film director Theo van Gogh. The great-grandnephew of the famous painter was shot and stabbed to death in 2004 in Amsterdam by a man with ties to a Dutch Islamist terror network.

Terror attacks in France since 2015 December 11, 2018: Strasbourg shooting A gunman opened fire at a Christmas market in the eastern city of Strasbourg, home to the European Parliament. At least two people were killed and 12 injured. Prosecutors opened a terror investigation. France immediately raised its national security alert to its highest level in anticipation of copycat attacks.

Terror attacks in France since 2015 May 12, 2018: Paris knife attack A man wielding a knife attacks bystanders in a central neighborhood in Paris, killing one person and wounding another four. French prosecutors open a terror probe into the attack, citing witness accounts that the assailant shouted "Allahu akbar" ("God is greatest"). The militant "Islamic State" (IS) group claims responsibility for the attack, calling the knifeman one of their "soldiers."

Terror attacks in France since 2015 March 23, 2018: Trebes hostage crisis An attacker claiming allegiance to IS perpetrates a string of violent crimes in the southern town of Trebes during the morning hours. He kills a man while stealing a car and then fires shots at police officers before entering a Super U grocery store, where he takes hostages. Police shoot dead the attacker. Four people are killed, including including policeman Arnaud Beltrame.

Terror attacks in France since 2015 October 1, 2017: Marseille train station knife attack A man fatally stabs two women at the Marseille train station. The perpetrator, Ahmed Hanachi, is shot dead by police on patrol. IS claims responsibility for the attack in a post by its news agency Amaq. In it, they call Hanachi one of the group's "soldiers." Two Interior Ministry officials resign after it is revealed that Hanachi was an undocumented immigrant who they had failed to detain.

Terror attacks in France since 2015 April 20, 2017: Champs-Elysees police shooting A gunman opens fire on police on the Champs-Elysees, Paris' most iconic boulevard. One police officer is killed and two individuals are injured before police shoot the gunman dead. A note praising IS is found next to the gunman's body. The terrorist group also claims responsibility. The attack occurs just days before the first round of the French presidential election. Security is tightened.

Terror attacks in France since 2015 February 3, 2017: Machete attempt at Louvre Soldiers shoot and severely injure a knife-wielding man outside the Louvre museum in Paris after he assails them. One soldier is lightly injured. The attacker had two further machetes in his backpack. A subsequent investigation reveals the Egyptian national had traveled to France from Dubai on a valid tourist visa. A Twitter account associated with the man's name refers to IS in posts.

Terror attacks in France since 2015 July 26, 2016: Murder of Normandy priest Two teens enter a church in Saint-Etienne-du-Rouvray, Normandy and slit the throat of an 85-year-old priest in front of five parishioners. Police shoot the 19-year-olds dead as they try to leave. IS takes responsibility and publishes a video of the teens pledging allegiance to the group. Many French Muslims attend the next Sunday's Mass to show solidarity with Catholics and condemn the attack.

Terror attacks in France since 2015 July 14, 2016: Truck attack in Nice On Bastille Day, France's national holiday, a truck drives through crowds in Nice that had gathered to watch the fireworks on a major seaside promenade. Before being shot dead by police, the driver kills 86 and injuries more than 400 others. IS claims responsibility, stating that the attacker had responded to IS calls to target civilians living in coalition nations fighting IS in Syria and Iraq.

Terror attacks in France since 2015 November 13, 2015: Paris attacks France's most deadly terror attack: IS jihadis armed with automatic weapons and explosives undertake coordinated attacks in Paris including at the Bataclan concert hall, the national stadium and various street cafes. The mass shootings and suicide bombings kill 130 people, injuring hundreds more. IS claims responsibility. Then-President Francois Hollande calls it an act of war by IS.

Terror attacks in France since 2015 August 21, 2015: Thalys train tragedy averted A deadly attack is averted: On a high-speed train from Amsterdam to Paris, a man opens fire with an assault rifle that subsequently jams. Other train passengers tackle the man, preventing deadly violence. Four are injured including the attacker. The assailant had been known to French security officials for past drug-related activities and statements in defense of radical Islamist violence.

Terror attacks in France since 2015 June 26, 2015: Beheading, truck explosion near Lyon Yassin Salhi beheads his boss and displays the head, along with two Islamic flags, on the gate outside a gas plant near Lyon. He also tries to blow up the factory by driving his van into the gas cylinders. The attempt fails, but unleashes a smaller explosion, injuring two. French authorities claim links between the man and IS. He commits suicide in prison.

Terror attacks in France since 2015 January 7-9, 2015: Charlie Hebdo, Jewish supermarket attack Two men with automatic guns storm the offices of satire magazine Charlie Hebdo, killing 12 and wounding 12 others. A different gunman kills a police officer the next day, then four more during a hostage-taking on January 9 at a kosher grocery. Police eventually shoot all three gunmen dead, but not before they claim allegiance to IS and al-Qaida. Author: Cristina Burack



amp, kw/aw (AFP, Reuters)

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