Officers launched a search and tracked down a 17-year-old, whom they arrested on suspicion of religiously aggravated criminal damage. He was taken into custody but later released without charge.
Other swastikas were reportedly sprayed on walls elsewhere in the area.
Researcher Luke Turner wrote on Twitter: “Came home last night to find my north London Jewish neighbourhood a crime scene, with swastikas daubed on every road round the synagogue. Was in two minds about posting, but it’s important to document the horror & trauma these symbols inflict on a whole community.”