The claims related to several articles by the journalist and commentator Māris Zanders, where he allegorically and indirectly hinted at the mobile phone numbers and home locations of several Latvian politicians. The idea was that these unnamed persons with indirectly described numbers and addresses could get calls, text messages or "visits" by citizens wishing to express their dissatisfaction (or praise, you never know) of the policies and behavior of the Latvian political elite.
The administrator of www.pingviniem.info, known by his first name Atis, has been asked to explain these articles in person at the Inspectorate on March 26. Details of the letter to Atis (in Latvian) can be found here. This summons could be considered the first serious attempt to harass the Penguins.
The Penguin Movement is an informal network of persons who support non-violent protests and direct action against what they see as an insensitive, arrogant and corrupt ruling elite in Latvia. It derives its name from a statement by former Prime Minister Ivars Godmanis in a New Year's Eve address that in cold weather (the present economic recession) the penguins (ordinary Latvian citizens) should huddle together.
My advice -- move the website to a US or other foreign hosting location which values freedom of speech (especially concerning public figures) above so-called data security issues.