She spoke after Moldova's Security Council held an urgent meeting prompted by two blasts which damaged masts that broadcast Russian radio in the region, where authorities said a military unit was also targeted.
The Moldovan authorities are sensitive to any sign of worsening security in Transdniestria, an unrecognised Russian-backed sliver of land bordering southwestern Ukraine, especially since the invasion of Ukraine.
"From the information we have at this moment, these escalation attempts stem from factions from within the Transdniestrian region who are pro-war forces and interested in destabilising the situation in the region," President Maia Sandu told a news conference.
She said the security council had recommended improving the combat readiness of security forces, increasing the number of patrols and checks near Moldova's border with Transdniestria and monitoring critical infrastructure more closely.
Russia has had troops permanently based in Transdniestria since the collapse of the Soviet Union.
Ukraine fears the region could be used as a launch pad for new attacks.
"In the early morning of April 26, two explosions occurred in the village of Maiac, Grigoriopol district: the first at 6.40 and the second at 7.05," Transdniestria's interior ministry said.
No residents were hurt but two radio antennae that broadcast in Russian were knocked out, it said.
Separately, Transdniestria's Security Council reported a "terrorist attack" on a military unit near the city of Tiraspol, Russia's TASS news agency reported.
It gave no further details.
Last week, a senior Russian military official said the second phase of what Russia calls its "special military operation" in Ukraine included a plan to take full control of southern Ukraine and improve its access to Transdniestria.
Kremlin spokesman Dmitry Peskov told reporters on Tuesday the news was a cause for serious concern and that Russia was following events closely.
Later in the day, the Russian foreign ministry said it wanted to avoid a scenario in which it had to intervene in Transdniestria, the RIA news agency reported.
Moldova's Sandu described the situation as "complex and tense" but said she had no plans to hold direct talks about it with Russian President Vladimir Putin.
Tuesday's incidents followed a number of blasts that local television reported on Monday hit Transdniestria's ministry of state security in the regional capital Tiraspol.
Local officials said the building had been fired on by unknown assailants with grenade launchers.
Transdniestria's unrecognised president's office has ordered the terrorist threat level to be raised to red and said that checkpoints would be set up at the entrances of the region's towns.
All vehicles entering at night would be checked, it said.
