The thwarted attack at France's Orly airport, where troops shot dead a man who grabbed a soldier's weapon, has been linked to the shooting of a police officer earlier north of Paris, police said.
The earlier shooting took place in the northern suburb of Stains on the other side of the city.
A man travelling by car opened fire during a routine stop-and-search operation, slightly wounding one officer in the head, police said.
The attack, which took place at around 6:55am (4.55pm AEDT) "is linked" to the foiled assault at Orly at around 8:30am (6.30pm AEDT), police sources said.
No-one was injured in the standoff at the airport, which was evacuated. All flights in and out of the airport were suspended.
France is still in a state of emergency after a series of terror attacks, including the November 2015 massacre in Paris and a truck attack in Nice, in July last year. In mid-February, an Egyptian staged a machete attack in Paris's Louvre museum before being shot and wounded.
The latest shooting comes weeks ahead of the first round of France's two-stage presidential election, in which security is one of the main issues on voters' minds.
"We had queued up to check in for the Tel Aviv flight when we heard three or four shots nearby," witness Franck Lecam said.
"We are all outside the airport, about 200 metres from the entrance," the 54-year-old said.
"There are policemen, emergency workers and soldiers everywhere in all directions. A security official told us that it happened near gates 37-38 where Turkish Airlines flights were scheduled."
The soldier from whom the man took the weapon was a part of Operation Sentinelle, deployed after the January 2015 Paris attacks.
It involves some 7000 troops of whom roughly half are deployed in the Paris region. They are charged with guarding religious sites which could be targets of terror attacks as well as airports, railway stations and tourist spots.
A notice was posted on the Paris airports authority website urging passengers not to travel to Orly.
Budget airlines easyJet said in a statement that "like all other airlines" it expected interruptions and flight delays, adding that 46 ot its flights were due to fly in and out of the airport on Saturday.
On Thursday, a letter bomb exploded at the Paris offices of the International Monetary Fund, injuring a secretary who suffered burns to her hands and face.
French President Francois Hollande called it an "attack", saying it showed the country was "still targeted".
"All this leads me to justify the state of emergency" that has been in effect since November 2015, Hollande said.
The Paris letter bomb coincided with a school shooting in the southern town of Grasse that left around 10 people injured and rattled nerves.