MELISSA BLOCK, HOST:

Today in Paris, after a moment of silence to honor the victims of last week's terrorist attacks, a lone voice in the French Parliament began singing.

(SOUNDBITE OF FRENCH NATIONAL ANTHEM, "LA MARSEILLAISE")

UNIDENTIFIED PARLIAMENTARIANS: (Singing in French).

BLOCK: The other members joined in on a spontaneous, rousing rendition of the national anthem. It was apparently the first time "La Marseillaise" had been sung in the National Assembly since 1918, at the end of the First World War.

(SOUNDBITE OF FRENCH NATIONAL ANTHEM, "LA MARSEILLAISE")

UNIDENTIFIED PARLIAMENTARIANS: (Singing in French).

BLOCK: Authorities in France have new leads in the case, but the deaths of the three main suspects have left many unanswered questions, including whether these men worked alone. NPR's counterterrorism correspondent Dina Temple-Raston joins me now from Paris. And Dina, do authorities there have an idea of how many more people may have been involved in these incidents beyond the three attackers who were killed?

DINA TEMPLE-RASTON, BYLINE: Well, we heard this morning Paris time about a new arrest in Bulgaria that appear to be linked to the attacks. Everyone thought that this might be the evidence of a sleeper cell of some sort, but we've confirmed that this man is a family member related to the shooters. We aren't quite sure what the relationship is, but he was initially held by Bulgarian authorities on charges that he was kidnapping his own son - some sort of custody problem. The French are trying to get him extradited. And it's unclear whether he was involved in these attacks at all. Police announced this morning that they were looking for six more people who they had linked to the attacks. But we understand that these are people they'd like to question, not necessarily arrest.

BLOCK: We also know, Dina, that there was a woman police were seeking - a fourth suspect who apparently traveled from France to Turkey and then on to Syria.

TEMPLE-RASTON: Right. Today there was new evidence. Turkish officials released surveillance video that showed her coming into Turkey at the border. And just to remind you, her name was Hayat Boumedien. And she was living with a gunman who was killed in the kosher market. But now it seems she had already left the country before that attack started. And she crossed the border with another man that they would like to question.

BLOCK: And based on what's known now, Dina, does this add up to being a terrorist cell in France?

TEMPLE-RASTON: Well, there's a lot of circumstantial evidence that others were involved. For example, there was a video of one of the suspects that was uploaded on Twitter and YouTube over the weekend, which suggests that there are more people involved since someone had to upload the video after the suspect died. You know, every day there seems to be a new twist in this case. This morning, for example, police officials revealed that Hayat Boumedien's car, this MINI Cooper, was seen driving in Paris over the past week. Remember, this is the woman they think is in Syria. So police want to question the man they've seen behind the wheel. He may be involved in the attacks, he may not. They don't know.

BLOCK: And, Dina, one of the big questions has been, based on the statements and videos from these attackers, is whether they were acting under the direction of al-Qaida or the Islamic State. Have officials there reached any conclusions about that?

TEMPLE-RASTON: Well, after about a week of looking, they can't find any connection to the Islamic State even though the gunman in the market said he had attacked on behalf of ISIS. They haven't found any indication that al-Qaida somehow directed this attack. They don't think any of the men traveled to Syria. They think only one of the men - one of the brothers thought to be behind the magazine attack - had direct contact with al-Qaida. But they can't find evidence that al-Qaida actually directed or launched this attack. One way to think about this attack is if you think of this on a scale with the Boston Marathon on one end, in which the Tsarnaev brothers apparently acted on their own, and the Underwear Bomber of 2009 on the other, where al-Qaida and Yemen provided the bomb, this is somewhere in between.

BLOCK: OK. NPR counterterrorism correspondent Dina Temple-Raston in Paris. Dina, thanks very much.

TEMPLE-RASTON: You're welcome. Transcript provided by NPR, Copyright NPR.