YANGON, Myanmar (CNN) — Myanmar opposition leader Aung San Suu Kyi was sentenced on Tuesday to 18 months of house arrest.

The sentence is significantly less than the maximum five-year prison sentence the Nobel peace laureate faced for the charges.

The case stems from a May 3 incident in which American John William Yettaw — a 53-year-old former military serviceman from Falcon, Missouri — swam two miles across a lake to Suu Kyi’s home and stayed for two days.

The government of Myanmar said Yettaw’s presence violated the conditions of Suu Kyi’s house arrest.

The court sentenced Yettaw to seven years of hard labor.

The trial began on May 18 at a prison compound near Yangon and was widely criticized by the international community.

The defense was allowed to call two witnesses, compared with more than a dozen called by prosecutors.

Supporters of Suu Kyi said the trial was meant to keep her confined so she cannot participate in the general elections that the junta has scheduled for next year.

An exact date for the elections has not been set. It is, therefore, unclear whether Suu Kyi’s house arrest will prevent her from campaigning.

Her lawyers have 60 days to appeal the conviction to a higher court. It was not immediately known whether they planned to do so.

The 64-year-old Nobel laureate has spent the last 14 of 20 years in one form of confinement or another — most recently under house arrest in a crumbling, colonial-era lakeside home.

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