  We prove that Killing horizons in massive IIA supergravity preserve an even
number of supersymmetries, and that their symmetry algebra contains an
$\mathfrak{sl}(2, R)$ subalgebra, confirming the conjecture of [5]. We also
prove a new class of Lichnerowicz type theorems for connections of the spin
bundle whose holonomy is contained in a general linear group.
