While NTSB investigators at South Bend Airport (SBN) in Indiana are searching for the cause of the March 17 crash of a Hawker Beechcraft Premier I, they are also wondering if there’s any connection between the SBN accident and two other Premier crashes in the past month. Nine people died in the three accidents.

A Premier crashed on March 4 just after takeoff from an airport in southeastern France, while a third Premier was destroyed on February 20 in a landing accident at Thomson-McDuffie County Airport, west of Augusta, Ga.

The South Bend accident claimed the lives of the two pilots when the aircraft first struck two homes before embedding itself in a third. Two passengers aboard that airplane survived with serious injuries. An FAA spokesman said the pilot of the jet in South Bend reported an unspecified mechanical issue shortly before the accident, while a pilot witness said the aircraft attempted to land twice on Runway 9 Right before crashing into the homes.

Beechcraft said in a statement that it “is cooperating with the National Transportation Safety Board and cannot comment due to the ongoing active investigations.”