This site was one of thousands of wordpress sites attacked by hackers who used a security flaw in a previous version of WordPress to corrupt two articles by altering some of the links to point to their own sites. That casued Google to label the site as “suspect”. I believe I have now removed the hackers code and the site is back to normal, and has been cleared by Google.
Apologies if anyone was affected by this, and I will increase security on the server to try to prevent it happening again.
Jacob