"It is a reminder that al Qaeda is a presence, and it can be a deadly presence, but whether this is al Qaeda or not is really too early to tell," said King on CNN's "Starting Point."
Reports from the French media have said the gunman declared ties to al Qaeda, but it has not been confirmed.
The same French town was the site of a shooting rampage in March that resulted in the deaths of three children and a rabbi outside a Jewish school, as well as the killing of three soldiers nearby.
French prosecutors at the time said the perpetrator in the earlier incident told negotiators that he was linked to al Qaeda, and that he committed the shootings in revenge for the deaths of children in Palestine and over Western intervention in Afghanistan.
The bank is in the same neighborhood where the suspected gunman in the March attacks, Mohamed Merah, was shot and killed by police, reported the AP.
King raised concerns that if the latest violence is liked to the terrorist group, it "raises it to a new dimension" because al Qaeda has not previously been involved in this type of attack.
However, the New York congressman emphasized that it's "too early to tell."
"It could be that he's just a bank robber that got caught and he's now trying to use al Qaeda as some kind of a shield to get himself into negotiations, maybe work a deal for himself," King added.
King also weighed in on the recently concluded G-20 summit of world leaders in Mexico, telling CNN the talks didn't appear productive.
"What I've seen of this summit so far, it did not seem to be overly productive. Now, again, it could be agreements we're not fully aware of, but as of now it did not seem to be very productive," he said.
However, President Obama said he was "encouraged by what he heard" from Angela Merkel on
Monday at the summit, where he urged the German chancellor
and other European leaders to move forward after the “positive
prospect” of Greece’s election.
King told CNN it is "vital" for Obama to come to an arrangement with European leaders to solve their economic crisis, given the impact it has on the United States.