Stealth journal takeovers, that is, the discreet acquisition of established academic journals by entities with questionable publishing practices, represent an emerging threat to the integrity of scholarly communication. This study proposes a set of bibliometric analyses to detect such takeovers, focusing on sudden shifts in citation patterns and authorship networks. Based on an analysis of 55 journals linked to a known network of related publishers, we identify substantial increases in cross-journal citations and shared authorship following ownership transitions, often between journals with no clear thematic connection. These patterns may serve as early warning signals for bibliographic databases and other academic stakeholders aiming to avoid compromised journals. Our findings also demonstrate the potential of scientometric methods to support the detection of problematic publishing practices, contributing to the growing field of forensic scientometrics.