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Remember the chimp at a Dutch zoo who emphatically swatted a TV crew’s drone out of the sky with a tree branch? Researchers who dissected Tushi’s actions have concluded she planned the attack, sort of like a human would.

In a study recently published in the journal Primates, Jan van Hooff and Bas Lukkenaar re-examine the events of April 10, when a Dutch TV crew was using a camera-equipped drone to film a documentary of chimpanzees at a 1.7-acre enclosure at the Royal Burgers Zoo in Arnhem.

Some of the chimps grabbed branches or twigs from willow trees and two females, Tushi and Raime, climbed up on scaffolding.

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As the drone got close, Tushi swatted at it twice with a 6-foot-long branch she brandished in her left hand. The second swipe made contact, knocking the drone to the ground. The camera continued to film, capturing the inquisitive faces of the chimps as they inspected and toyed with the perplexing gadget.

Related: Chimps Might Have More Evolved Hands Than Humans

The study’s authors note that Tushi grimaces just before and during the act of striking. “The precise coincidence of the facial grimace with the strike suggests that it is a concomitant of an assertive and determined exertion of force, homologous to what humans do in comparable situations.”

The researchers note that Tushi collected the stick before the drone approached, and carried it to a place where the drone might be swatted. The sequence of events, they say, suggests the attack was "planned" and "deliberate."

"This episode adds to the indications that chimpanzees engage in forward planning of tool-use acts," they write.