The revised anti-stalking law, passed in June in response to recent high-profile murder cases involving stalkers, took effect Thursday.

The revision, the first since the law was enacted in November 2000, requires the police to explain to a victim in writing if they don’t issue a warning to a stalker. It also requires that the police notify a victim when a warning has been issued.

The revision also makes it possible for police with jurisdiction over where offenders live or stalking is taking place to issue warnings and restraining orders, rather than just where the victims live.

Before the revision, many victims hesitated to report to police out of concern that offenders would find out where they live, as past cases have shown that stalkers used the information on the warning listing the name of the city where the victims resided.

Harassing emails are now considered a form of stalking, in addition to fax messages and telephone calls. The addition of electronic mail took effect in July, prior to the full revision coming into force.

The law as it now stands, however, does not cover threats using social-networking services or other forms of online communications. In an additional clause, the revised law states that an expert panel will be established to examine further improvements.

The National Police Agency will soon establish the panel, which will include representatives of victim-support organizations.

According to the NPA, as many as 19,920 stalking cases were recognized by police nationwide in 2012. That was the highest number since the anti-stalking law was introduced in 2000.

The stalking issue was brought into the spotlight in 2012 when police were criticized for their reluctance, and ultimately their failure, to protect victims who had reported being harassed.

In November 2012, a newlywed living in Zushi, Kanagawa Prefecture, was stabbed to death by an ex-boyfriend even though she had reported to the police that he had sent more than 1,000 emails to her cellphone in a two-week period. Reports said the killer learned of her new name and address from the police.