```python
import numpy as np
from pyscf import gto, scf, grad, mp, lib
from pyscf.grad import mp2 as mp2_grad

def generate_mm_particles(num_particles=5):
    np.random.seed(0)  # For reproducibility
    coordinates = np.random.rand(num_particles, 3) * 10  # Random coordinates in a 10x10x10 box
    charges = np.random.randint(1, 3, size=num_particles)  # Random charges between 1 and 2
    return coordinates, charges

def calculate_force(mol, mm_coords, mm_charges, method='HF'):
    if method.upper() == 'HF':
        mf = scf.RHF(mol).density_fit()
        mf.kernel()
        dm = mf.make_rdm1()
        grad_method = grad.rhf.Gradients(mf)
    elif method.upper() == 'MP2':
        mf = scf.RHF(mol).density_fit()
        mf.kernel()
        mp2 = mp.MP2(mf).run()
        dm = mp2.make_rdm1()
        grad_method = mp2_grad.Gradients(mp2)
    else:
        raise ValueError("Unsupported method: {}".format(method))

    # Calculate the force on MM particles
    force = np.zeros_like(mm_coords)
    for i, (coord, charge) in enumerate(zip(mm_coords, mm_charges)):
        for j in range(mol.natm):
            qm_charge = mol.atom_charge(j)
            r = coord - mol.atom_coord(j)
            force[i] += qm_charge * charge * r / np.linalg.norm(r)**3

        # Interaction between electron density and MM particles
        for grid_coord in lib.cartesian_prod([np.linspace(0, 10, 10)]*3):
            r = coord - grid_coord
            density_at_grid = grad_method.get_veff(mol, dm, grid_coords=grid_coord.reshape(-1,3)).reshape(-1)
            force[i] += charge * density_at_grid * r / np.linalg.norm(r)**3

    return force

# Define a molecule
mol = gto.Mole()
mol.atom = 'H 0 0 0; F 0 0 1.1'
mol.basis = 'sto-3g'
mol.build()

# Generate MM particles
mm_coords, mm_charges = generate_mm_particles()

# Calculate and print the force from HF electron density
hf_force = calculate_force(mol, mm_coords, mm_charges, method='HF')
print("HF Force:\n", hf_force)

# Calculate and print the force including orbital response from MP2 electron density
mp2_force = calculate_force(mol, mm_coords, mm_charges, method='MP2')
print("MP2 Force (with orbital response):\n", mp2_force)
```