According to a spokesman who talked to the newspaper Svenska Dagbladet, Sweden’s coast guard spotted a fourth gas leak on the damaged Nord Stream pipelines earlier this week.

The European Union has pledged a “strong” response to any deliberate interruption of its energy infrastructure and believes that sabotage was responsible for the gas leaks on the underwater Russian pipelines to Europe.

“Two of these four are in Sweden’s exclusive economic zone,” coast guard spokesperson Jenny Larsson told the paper late on Wednesday. The other two breaches are in the Danish exclusive economic zone.

Both pipelines were packed with gas that has been gushing out into the Baltic Sea since Monday’s ruptures, even though neither was in operation at the time of the suspected explosions.

The fourth leak was discovered on the Nord Stream 2 pipeline, not far from a bigger hole discovered on the adjacent Nord Stream 1, according to the Swedish coast guard.