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Lego bricks aren't all fun and games, University of Canterbury researchers argued in a study published in Plos One, a peer-reviewed open-access journal. They're increasingly promoting violence in their products, the researchers said.

Nearly 30 percent of Lego sets out in 2014 contained weapons, compared with less than 5 percent in 1978, the first year the manufacturer included them in sets. Themed products for franchises like The Lord of the Rings and Star Wars are thought to have contributed to the uptick, as well as competition with other toy makers.

"To catch the attention of their customers, toy manufacturers are similarly locked in a metaphorical arms race for exciting new products," the study authors wrote.

Lego, for what it's worth, doesn't consider the presence of weapons in its toys an endorsement of real-life violence.

"We do not make products that promote or encourage violence," a Lego spokeswoman told BuzzFeed News. "Weapon-like elements in Lego sets are part of a fantasy/imaginary setting, and not a realistic daily-life scenario."

To read more about the researchers' methodology, which gets deep into the weeds of whether the bricks used to make a Death Star should be considered weapons, head over to Plos One.