India has lodged a protest with Pakistan for alleged harassment of Indian High Commission officials in Islamabad between March 8 and March 11, ANI reported.

The Indian High Commission issued a note verbale to Pakistan Foreign Ministry on March 13, with details of incidents including tailing of India’s deputy high commissioner, naval adviser and a first secretary on multiple occasions, unidentified officials told PTI. Some reports, however, said the note verbale was issued on Monday.

India cited 13 instances of alleged harassment in the month of March and urged Pakistan to investigate the matter.

The note verbale said two Pakistani security personnel were following the India high commissioner. It said Pakistani security agency personnel had aggressively tailed the first secretary and the naval adviser in a car on March 8. The following day, India’s deputy high commissioner was followed by Pakistani personnel on a motorcycle while he was going from his residence to a market and again while travelling from the Indian mission to his residence, the Hindustan Times reported, citing unidentified officials.

Pakistani security personnel were also spotted keeping surveillance outside the deputy high commissioner’s residence on March 9 and March 10. The note said the naval adviser in the India mission was followed by Pakistani security personnel on March 8, March 9, March 10 and March 11, according to PTI.

The Indian High Commission sought Pakistani authorities to investigate the incidents, saying such cases of harassment were a violation of the Vienna Convention on diplomatic relations.

Tensions between the two countries escalated after India claimed to have carried out air strikes on a Jaish-e-Mohammad camp in Pakistan’s Balakot on February 26 in response to a terrorist attack on a Central Reserve Police Force convoy in Kashmir’s Pulwama on February 14, which killed 40 soldiers. A day after the cross-border strike, India and Pakistan engaged in aerial skirmishes.

In January, India accused intelligence agencies of Pakistan of intercepting and threatening two staff members of the Indian High Commission in Islamabad.